What does “capital growth forecast” actually mean for a pre-commercial coastal market?

In a mature market — Canggu, Singapore, central Lisbon — a capital growth forecast can lean on transaction registries, year-on-year price indices, and rental yield curves to produce a defensible compound annual figure. Kertasari does not have those instruments. There is no published price index for Kabupaten Sumbawa Barat. Transaction volumes are low enough that any single transfer skews a thin sample. Public rental-yield data is, in the pillar’s plain language, insufficient to model.

What Kertasari has instead is a price spread against more mature comparables on the same archipelago, and a set of infrastructure variables whose movement determines whether that spread closes. A credible 2026 capital growth forecast for Kertasari beach property therefore takes the form of a conditional: if Kiantar Airport stabilises commercial scheduled service, and if the Kertasari peninsula road network upgrades, and if Bali-substitute capital arrives at scale, then the Kertasari band compresses toward Lombok’s. The size of the compression and the time horizon are the variables.

A reader who wants a single number can always be sold one. What they cannot be sold honestly, at this stage, is the inputs that would produce one.

What drives capital appreciation in pre-commercial coastal land?

Capital appreciation in coastal land that has not yet been institutionalised tracks four drivers, in roughly the following order of weight.

• Air access. Coastal land trades on connectivity to capital. A market two flights and a ferry from a major hub trades at a steep discount to a market one direct flight from the same hub. Bali’s pricing premium over Lombok is partly an air-access premium. Lombok’s premium over Sumbawa is the same effect one step further out.
• Road access and last-mile infrastructure. Once a buyer is on the island, the time from runway to villa parcel matters. The Kertasari corridor is approximately 20 minutes by road from Kiantar Airport at Poto Tano. Whether that 20 minutes holds — and whether the road condition is upgraded — affects how the parcel is experienced by future buyers and renters.
• Legal regime stability. Indonesian foreign-ownership rules have been broadly stable in principle since UUPA was enacted in 1960, and were liberalised at the company level in October 2025 with BKPM Regulation No. 5 of 2025. A stable regime supports orderly secondary trading; an unstable one prices a discount.
• Comparable-market pricing. Coastal land is priced relative to the nearest functioning comparable. Kertasari’s nearest functioning comparable for premium beachfront is South Lombok and Mandalika, at approximately USD 100–250 per square metre. The Kertasari range of approximately USD 83-84 per square metre sits one step down. The spread is the forecast’s raw material.

None of these drivers gives a percentage. Together, they give a direction and a sense of magnitude.

How does Kertasari beach property compare to Bali and Lombok in 2026?

The clearest way to anchor a forecast is to put the three markets next to one another. Foreign-ownership pathways are identical across all three; pricing and infrastructure stage are not.

Metric	Bali (Canggu / Bukit)	South Lombok (Mandalika)	Kertasari corridor (West Sumbawa)
Premium beachfront land	USD 600–1,000+/m²	USD 100–250/m²	USD 83-84/m²
Foreign ownership pathways	Hak Pakai, leasehold, PT PMA	Same	Same
PT PMA paid-up capital (Oct 2025)	IDR 2.5 billion	IDR 2.5 billion	IDR 2.5 billion
Reported rental yield (premium villa)	6–10%	8–10%	Insufficient public data
PPAT / notary capacity	High (Badung)	Moderate	Low (Kabupaten Sumbawa Barat)
Air gateway	DPS, ~30+ airlines	LOP / BIZAM, ~2.5M pax 2025	Kiantar (Poto Tano), commissioning
Market stage	Mature, congested	Growth, mid-stage	Pre-commercial

The numerical question for the forecast is the size of the gap between USD 83-84 in Kertasari and USD 100–250 in South Lombok, expressed as a closure trajectory. If the spread closes from a mid-point of approximately USD 100 toward a mid-point of approximately USD 175 over a 5-to-10-year horizon, that is the directional shape of the thesis. Whether it closes that fast, more slowly, or at all depends on the infrastructure variables in the next section. Closure is a possibility, not a promise.

For the broader market context underneath this table, see our West Sumbawa land banking pillar.

What does the Kiantar Airport timeline mean for Kertasari capital growth?

Kiantar Airport at Poto Tano, in the northwestern corner of Kabupaten Sumbawa Barat, is the single most important infrastructure variable for the Kertasari forecast. It is owned and developed by PT Amman Mineral Nusa Tenggara, the operator of the Batu Hijau copper-gold mine, and was originally built to serve corporate operations. Commissioning began in March 2025; a phased opening to commercial domestic service was announced by the Bupati of Kabupaten Sumbawa Barat in February 2025. Current scheduled-route status should be verified with a primary source — PPID Kabupaten Sumbawa Barat, a PT Amman Mineral disclosure, or a Wings Air / Lion Air route announcement — dated within 60 days of any binding decision.

For comparison, Lombok International Airport (BIZAM) across the strait handled approximately 2.5 million passengers in 2025 across a mature international and domestic route base. The Kertasari forecast does not require Kiantar to match BIZAM’s throughput. It requires Kiantar to remove the multi-segment journey — flight, ferry, transfer — that currently makes Sumbawa a five-step itinerary for a Bali- or Singapore-based buyer.

The mechanism by which an airport opening affects land prices is well-documented in regional precedents. South Lombok’s pricing curve accelerated meaningfully in the years following Lombok International Airport’s relocation and Mandalika SEZ designation. Kertasari is not Mandalika and should not be modelled as such; the corridor lacks an SEZ designation and has a different demand profile. The directional precedent, however, is real. If Kiantar’s commercial scheduled service stabilises, the spread compresses. If it slips by a year, the discount holds a year longer.

What does the PT PMA / HGB legal structure mean for capital protection in Kertasari?

Capital growth requires capital protection. The legal pathway under which a foreign buyer holds Kertasari beach property is the same in 2026 as it has been since UUPA was enacted in 1960, with one material 2025 change to the company structure.

Buyers acquire a 90-year leasehold (Hak Sewa), registered at BPN; no freehold is offered..

The October 2025 change worth noting in the 2026 forecast is BKPM Regulation No. 5 of 2025, which lowered the PT PMA paid-up capital threshold from IDR 10 billion to IDR 2.5 billion, while retaining a separate IDR 10 billion total investment plan. The effect on Kertasari is to broaden the pool of foreign buyers who can credibly underwrite an HGB-via-PT PMA position, which in turn supports a deeper secondary market over time. The operational detail of the legal pathways is covered in our Buying Property in Sumbawa as a Foreigner pillar.

What can a buyer actually model — and what should they refuse to model?

Three things a Kertasari buyer can reasonably model in 2026.

• The spread. The gap between Kertasari pricing and South Lombok pricing is observable and updatable. A buyer can track Mandalika comparables annually and recalibrate their assumed closure rate.
• The infrastructure timeline. Kiantar Airport’s published flight schedule, the BIZAM passenger figure, and the condition of the Kertasari peninsula access road are all observable. They are not predictable, but they are observable, which is the point.
• The legal cost stack. BPHTB at 5% of taxable value on the buy side, PPh at 2.5% of transaction value on the sell side, PT PMA establishment and maintenance costs on the corporate side, and PPAT and BPN fees on the registration side are all known and quotable in advance.

Three things a Kertasari buyer should refuse to model.

• A fixed annual percentage return. There is no transaction registry capable of producing one credibly. Anyone who supplies one has either sourced it from a related transaction or invented it. Ask which.
• Rental yield as a Kertasari yield. Premium villa yields quoted for Bali (6–10%) or Lombok (8–10%) are not transferable to Kertasari, where occupancy and rate data are not publicly available. Treat any rental-income projection as a sensitivity assumption, not a forecast input.
• A precise spread-closure date. If the model only works on a specific timeline, the model is too tight for the asset class. Sensitivity-test the horizon between 5 and 10 years and the closure rate between 25% and 75% of the gap.

What are the real risks that could compress or extend the Kertasari thesis?

Four risks should be priced before signing a PPJB.

• Infrastructure timing. Kiantar Airport’s commercial scheduled service is the largest single variable. Slippage extends the discount.
• Liquidity and secondary market depth. Kabupaten Sumbawa Barat has limited PPAT capacity, limited brokerage infrastructure, and a thin pool of qualified secondary buyers. Selling a Kertasari plot in year 2 is materially harder than selling a Canggu plot in year 2. Position sizing should reflect this.
• Title and zoning diligence. Sempadan pantai (coastal setback) lines, RTRW (regional spatial plan) zoning, and unresolved adat (customary) land overlap are all live issues, exactly as they are in Lombok and Bali. Independent PPAT diligence at the Kantor Pertanahan Kabupaten Sumbawa Barat (BPN) office in Taliwang is non-optional. Verify the original Sertifikat and confirm paid PBB for the past five years.
• Macroeconomic regional risk. Indonesian property is exposed to rupiah / USD movement and to changes in the regulatory regime governing PT PMA and HGB. The October 2025 changes were liberalising; future changes may not be.

Where does Rinjani Bay sit in the Kertasari capital growth conversation?

A capital growth forecast for the Kertasari corridor as a whole is not the same as a capital growth forecast for any single estate within it. The two diverge on what each estate adds to or subtracts from the corridor baseline.

Rinjani Bay is one of several active developments along the Kertasari coastline. The estate is a 46-hectare master-planned position with approximately 650+ metres of private beach frontage on the Lombok Strait. Two facilities — a Beach Club at beach level and Kebun Mantar, a working organic kitchen garden — are operational on site. A villa programme, Saka Bhuana, is under construction. The estate is held under a PT PMA structure with AMDAL documentation on file, available to qualified buyers on request. Approximate drive time to Kiantar Airport is 20 minutes.

From a capital growth perspective, what an institutional master plan adds over raw Kertasari land is the reduction of vapour risk: a registered holding company, a registered HGB title, a registered environmental impact assessment, and an operational amenity surface that a future buyer can stand inside before signing. These are not yield drivers. They are resale drivers. They affect the “saleable to whom” question that determines whether a position can be exited at the spread-closure price five or eight years out.

None of this guarantees the spread closes. It improves the odds that the position can be exited if and when it does.