It depends, check your mortgage terms, rezoning, or similar acts of government many times do not necessitate a term change in a fixed rate loan.

If your property is not in litigation now, it may be soon (check the property records for a lis pendens against the unit you want to buy).It sounds like the property you are thinking about buying may have been foreclosed by the HOA after the 2015 modifications to the foreclosure laws, which may avoid certain legal headaches that have been created by the 9th circuit court of appeals (see: https://cdn.ca9.uscourts.gov/datastore/opinions/20...)However, you will also want to check out which federal agencies may own an interest in your hoa lien.

However, my experience is that around two-thirds of people who demand contract modifications for basic services like this are often a PITA and keep trying to milk you for more and more as time goes on.

@Jingru Sui instead of a master lease I basically created my own rental lease that includes written consent to sublease, home modifications, and a few things that were relevant to my objective.

You may need to allow them to pay for some reasonable modifications to the property, however they will be required to return it to the condition at the end (Or leave the mods in place and rent it that way for the next tenant).Just my thoughts and good luck.

I also committed to fixing the sidewalk and external repairs to make the street look just that little bit better, as well as not requiring any major modifications to the building - paint, flooring, tile, etc.

From what I’ve seen unpermitted modifications are all over the place here in CA so I would bet that the base space is permitted, but there may be some unpermitted changes like the addition of bathroom and kitchen plumbing.

I went from walking away with about 8k to bringing almost 13k due to the modification.

A fixture by definition is something that is 'fixed' in place and to remove it, necessitates doing damage to the premises.

If its a mid-rise (4+ floors) you generally find that shut off valves in apartments are corroded and don't work necessitating you to shut the entire tier/line to do a simple repair.