Smart property tools for owners, landlords and buyers

That is the whole formula, and still it often goes wrong. The two classics: using the wrong starting index (the one at entry into force instead of at signing, or the other way round, depending on whether the lease predates 2019), and indexing from the date of the letter instead of the anniversary of the lease.

The calculator therefore first asks which kind of lease you have and which dates it carries. It then shows the new amount, the index figures used and a chart of the rent year by year since the start. That chart makes visible in one picture what a skipped year has cost.

For leases on a property with EPC label D, E or F, the tool applies the Flemish correction. It lowers the indexation of energy-hungry homes and keeps working in later years, even now that the measure itself has ended.

Indexation does not happen automatically. It only takes effect once you ask for it, and you can go back three months at most. An owner who only thinks of a March anniversary in November loses eight months. Every year again, because next year's base starts from what you ask for now.

The letter carries over the result of the calculator: old rent, new rent, the index figures used, the date from which the new amount applies. You add your details and your tenant's, and you get a PDF to print or email.

Property tax, service charges that stay with you, insurance, maintenance, vacancy between two tenants, the costs at purchase: each of those items eats into the same figure the seller quoted.

The analysis puts them side by side and shows what is left net, per month and per year, together with the payback period. Useful before you buy, and just as useful for a property you have owned for years: owners sometimes discover only then that the rent has fallen behind the market.

That is the point which surprises most owners: for ordinary residential letting, the rent plays no part in the tax return. Let to a company, or let a tenant use the property professionally, and the regime flips: the actual rent is taxed, after a flat cost deduction of 40 percent capped at two thirds of the cadastral income times the revaluation coefficient.

The difference between the two regimes is wide enough to build a decision on. The tool works through both with your cadastral income, your rent, your municipal surcharge and your average tax rate, and then shows what rent you would have to ask to keep the same net amount when letting to a company.

The Flemish residential lease decree has fixed that split since 2018. In practice the argument is rarely about water or electricity, but about the managing agent's invoice and about the lift. There the split is 34 percent for the tenant and 66 percent for you, and half and half for the periodic maintenance of the lift.

The module starts from your latest statement. You enter what you paid per item and you see straight away which part you may pass on and which part you may not. That avoids the most unpleasant discussion there is, the one afterwards, with a tenant who does not understand the statement.

One item always stays with you: property tax can never be charged to the tenant when letting a main residence, not even with a clause in the lease.

That is something other than a valuation, and that distinction is half the story here. The index says what your money is worth, not what your home is worth. A terraced house in central Ghent and a country house in the Flemish Ardennes follow the same index and not the same market.

What it is good for: setting a floor and correcting a gut feeling. Someone who bought in 2009 for 210,000 euro and hears 240,000 euro today thinks there is a gain and there is none. If you then want to know what the market itself says, we come by for a real valuation.

The overview tool asks those three questions and then puts your list together, split into required, strongly advised and conditional. You can take it with you as a PDF and tick items off as the documents come in.

It is the kind of work nobody likes to do early and that always costs time later. A soil certificate takes a few days, an asbestos certificate longer, and one missing document holds up a sale agreement on the day everyone is already at the table.

Keep an eye on the dates ahead as well. The measures register has been required on a sale since 1 April 2026, and from 1 January 2027 selling an apartment in a building from before 2001 will also require an asbestos certificate for the common parts.