Land value by initial yield on cost with your assumptions (what-if)

The land value of a Swiss parcel by initial yield on cost (RICS Valuation of development property, 1st ed. 2019, B2.2.3.4): the annual income on completion of letting over the total development cost. Read backwards at a target yield (default 5% on gross rent), it caps the total development cost, and the land value is what remains after construction (default CHF 4,000/m² NIA), professional fees (12%), contingency (5%), letting expenses, finance (3% over 24 months) and site acquisition costs (2.5%).

What it is. A development land value: the parcel built out to its buildable area (land × the average utilization of its zone in its municipality) with rents from the municipality's market data. It is not the market value of what stands on the parcel today. A negative land_value is a valid answer: at these costs the rents do not reach the target yield, so development is not viable at that target.

Engine. The valuation is revenoo's (https://revenoo.aireon.ch): this route proxies revenoo's public yield-on-cost part and returns its body unchanged (links.docs documents every field, links.app opens the same valuation in revenoo). Units ride in the key: no suffix is an amount (CHF, rounded), _pct is percent (5 means 5%), _m2 square metres.

Auth / errors. token header. Send X-RES-API-Version: 2 to receive real 4xx/5xx statuses with a JSON body.

What-if. Send any of revenoo's documented assumptions (every response lists the ones it used under assumptions), e.g. target_yield_on_cost_pct, yield_on_cost_basis, construction_cost_per_m2_nia, finance_rate_pct, development_period_months, asking_land_price, rents and areas. Unknown keys and out-of-range values are rejected with 400 and details (one { key, message } per problem). Never cached.

POST

https://res.aireon.ch/res_api/valuation/yield-on-cost

Authorization

ResApiToken
API key in header
required

Request body JSON required

egrid
optional
string
Swiss parcel identifier (CH + 12 alphanumerics).
lat
optional
number
maximum: 47.9 · minimum: 45.7
lng
optional
number
maximum: 10.6 · minimum: 5.9
assumptions
optional
object
revenoo assumptions to change; omitted keys keep the defaults the response reports.

Returns

200

The yield-on-cost valuation with the assumptions applied.

JSON

api_version
optional
string
valuation_date
optional
string
format: date
parcel
optional
object
EGRID, address, municipality, BFS number, canton, zone, coordinates, land area, buildable GFA and rentable area (m²).
data
optional
object
Provenance: market data status and date, municipal and Zürich reference rents.
links
optional
object
app opens this valuation in revenoo; docs is revenoo's OpenAPI contract.
yield_on_cost
optional
One of the following:
YieldOnCost
land_value
optional
number | null
Land value at which the initial yield on cost meets the target (CHF). Negative when development is not viable at the target.

per_m2_land
optional
number | null
Land value per m² of parcel area.

per_m2_nia
optional
number | null
Land value per m² of rentable area (NIA).

target_initial_yield_on_cost_pct
optional
number | null
Target initial yield on cost, percent.

income_basis
optional
gross_rent
or
noi_before_capex
or
noi_after_capex
The annual income the yield is read on.

annual_income
optional
number | null
Annual income on that basis (the numerator).

income
optional
object
Gross potential rent and NOI before / after the capex reserve.

max_total_development_cost
optional
number | null
Annual income ÷ target yield: the total development cost the target allows.

development_costs
optional
object
Construction cost per m² NIA and in total, professional fees, contingency, letting expenses, finance rate (percent), development period (months) and finance on the development costs.

available_at_completion
optional
number | null
What the maximum total development cost leaves for the land at completion.

finance_on_land
optional
number | null
Finance on the land over the development period.

available_for_land
optional
number | null
What is left for the land and its acquisition costs, at purchase.

site_acquisition_costs
optional
number | null
Site acquisition costs on the land value.

at_asking_price
optional
object | null
With an asking_land_price assumption: that price, the total development cost and the initial yield on cost it gives (percent). Null otherwise.

sensitivity
optional
object | null
5×5 grid of land values: target yield (rows, percent) × construction cost per m² NIA (columns); current marks the base case.

method
optional
string
sources
optional
array of
object
null
}
assumptions
optional
object
Every assumption the valuation used.

400

Missing or invalid EGRID / point, or invalid assumptions (details lists each).

JSON

error
string
required
Human-readable error description.
message
optional
string
Optional underlying error message.

401

Missing token. (v2 callers only.)

JSON

error
string
required
Human-readable error description.
message
optional
string
Optional underlying error message.

403

Wrong token. (v2 callers only.)

JSON

error
string
required
Human-readable error description.
message
optional
string
Optional underlying error message.

404

No parcel with this EGRID, or none at this point.

JSON

error
string
required
Human-readable error description.
message
optional
string
Optional underlying error message.

429

The valuation service is busy; retry after the Retry-After seconds.

JSON

error
string
required
Human-readable error description.
message
optional
string
Optional underlying error message.

500

Unexpected error.

JSON

error
string
required
Human-readable error description.
message
optional
string
Optional underlying error message.

502

The valuation service failed.

JSON

error
string
required
Human-readable error description.
message
optional
string
Optional underlying error message.

504

The valuation service timed out.

JSON

error
string
required
Human-readable error description.
message
optional
string
Optional underlying error message.