That pause makes sense. I would run three cases: ordinary year, tenant-change year, and building-expense year. Do not assume vacancy, extra management and major repairs happen neatly in different periods; combine them in the downside case.
Also confirm which council, water, insurance and...
The practical decision is whether this purchase still leaves your chosen emergency floor intact after all known near-term costs. Confirm the settlement adjustments and first-payment date with the relevant people, price urgent inspection items, map the service charges, and stage non-essential...