Haven't heard of any requirements for a plan, can you elaborate? Afaik, you own the plot and can leave it shitty if you want as long as it's not a safety hazard.
> Often buyers are legally required to rehab these homes to bring them up to code. In Detroit, buyers are required to sign Affidavits of Compliance Responsibility, which obligates them to make repairs outlined in an inspection report. Only after that can a certificate of occupancy will be issued, which makes the house legal to live in.
Found this, seems to only apply for a certificate of occupancy (meaning you could let it sit as a long-term investment hoping the rest of the city improves to the extent your property value rises enough to make renovation an easy profit) not sure if it's what you're referring to.