A rented flat shows its ongoing payments in the normal plan. You want to know which additional amount you will need during an assumed vacancy period. The correct answer does not automatically arise from “three months’ rent plus three loan instalments”. Both figures point in different directions and may already be included in your normal plan.
This separate calculation is not an estimate of a typical vacancy duration. It also does not make any statement about which costs can legally be passed on or are tax-deductible. For that, concrete documents and individual advice are required.
Show the normal month fully first
In the hypothetical case, €900 of actually usable rent is received monthly. The simplified payment plan contains a €750 loan instalment and €100 of other payments borne by the owner. Under only these assumptions, €50 remains each month. Further expenses, taxes and irregular works are not yet accounted for here.
This limited starting position is documented. If your actual normal plan already contains its own vacancy item, the new scenario must not be superimposed on it without explanation. It replaces or changes an assumption.
Place the missed month alongside it
For three freely assumed months the €900 income falls away entirely. The stated outflows of a total of €850 continue to run in the example. The immediate additional financing requirement for those three months is then €2.550.
The difference compared with the original plan, however, amounts to €2.700: three times €900 are missing. That contains €2.550 of necessary coverage and €150 of originally expected surplus now absent. Both statements are correct, but they answer different questions.
Record additional transition expenses separately
If a renovation or re-letting is assumed, add only the specifically justified amount at its intended date. Do not use an automatic flat rate or a guarantee that money will start coming in again immediately afterwards. An open timing remains an open risk.
Also check whether the funds kept available are already needed for other obligations. An amount that is sufficient on paper is not freely available if it must be spent elsewhere in the same month. The level of an appropriate reserve is not specified here as a flat rate.
Ask the right question of your own planning
For the next decision the questions are: What must actually be paid during the period of loss? Which expected surplus is additionally lost? And which new expense is added? This separation helps avoid understating the requirement or artificially doubling it by adding instalments already recorded. It does not replace a comprehensive investment appraisal.