Short answer
Use viewings and refurb quotes to turn assumptions into evidence. The numbers are only as useful as the diligence behind them.
How it works in Koreograph
Viewing notes, images, checklist items, quick comments, calendar actions and refurb quote items can stay attached to the opportunity. Comments from viewings can be linked back to the viewing so the audit trail stays clear.
Developer view
Record damp, roof, electrics, layout constraints, access, planning concerns, rental demand and contractor feedback while it is fresh. Then adjust the scenario rather than leaving the original assumption untouched.