List the turnover costs individually rather than using one vague allowance: empty time, cleaning, repairs attributable to wear or damage as appropriate, advertising or leasing costs, and the owner’s time. Do not count upgrades that were due anyway entirely against changing tenants.
Micro-location would be my first question after lease length. “Good location” is too broad for valuation: outlook, noise, access within the development and the position of the block can explain a difference that looks like a condition adjustment.
For next steps, make a one-page grid with the...
For building charges, request the current amount, payment frequency and the method used to divide charges among owners. Also ask whether any already-approved work or unpaid balance could be allocated to this unit. Those are practical completion questions, not just annual budgeting.