In speaking with one of the neighbors I learned that the owner is in an adult facility and not expected to return. 

When each unit is expected to be renovated, what stage each renovation was in, how much was spent on it, the rent they were able to get on the completed ones, etc.

There should be some form of regular interest payments that are similar in frequency and rate to what your brother should expect if he were to go to an unrelated party in the open marketplace.   

Places that you wouldn’t expect people to be underwater on their mortgages.

Show that you have compassion and are willing to listen, maybe even apologize for misunderstandings or expectations not met.

Additionally, we can expect extra rental income in the offseason through airbnb. 

If you break that down, Im expecting approximately:50% of total return from market appreciation25% of total return from amortization25% of total return from current free cash flowSorry - got off track from your original question.  :-). 

How long did it take, what were you expecting to pay, etc.?

Ex: if you expect a furnace to last 15 years with an 1500$ replacement cost, and yours is 10 years old when you buy the property, then you should have a total of $1500 reserved in the next 5 years.

What is the expectation for how much these services cost for landlords?