Also, if there are any potential issues with pollution such as inground tanks, you need to know that you own the cleanup as the property owner.

It is condemned, the owners are hoarders, the husband is fighting for his life with cancer, they're doing a several-month-long-DIY move to Tennessee that they must be losing money on.  

The owner wants to minimize the capital gains tax he pays so we want to suggest to him to do a master lease to us for "x" amount of time, and we pay his lease fee and hold the rest of the money in this time we will secure a loan to buy using the money we make as part of the down payment.

We are just talking about dollars but they also suck way more time in management.Infrastructure- Apart from the utility infrastructure I want you to think of amenities like improved roads, pools, clubhouses etc Delinquent Tenants and Poor Management- It is not unusual to purchase communities where the owners have not been completely forthright with their rent collection.

Check to see if your jurisdiction is SB9 friendly and check the zoning on the current parcels  ADUs can be rented long term regardless of owner occupancy on the property.  

I feel uncomfortable asking to walk the property with a contractor because I don't have an established relationship with a contractor, am not confident the deal will pencil without the rehab estimate, and would need the owner to approve the walkthrough even though some units are occupied. 3.

@David Yandel at least 95% of agents only know how to buy-sell owner-occupied properties - which are sold on emotion.Investment properties should be bought & sold by the numbers, which most agents don't take the time to learn and actually ASSIST their clients.

Tools like AirDNA are also not giving would be STR owners the true picture. 

She had moved in before we bought the condo, and the equipment change was required for the cable TV and internet service to continue as the prior owner would of course cancel their account after closing. 

Can usually allot 5-10% vacancy factor and same for maintenance.Class B usually also okay, but needs more attention from owner and/or PMC.