We purchased our primary property here in Hawaii in 2021 and have found immense benefit from the property setup which allows us to rent out our "ohana" unit (mother in law) which covers our mortgage costs.

Find othere cost saving iteams  on maintenance and capital improvements like LVT in the bedrooms ect. 

A few things to consider: are you increasing rent each year to at least try to recoup some of the additional costs (everything goes up, so why should the family member not pay more-if it is your parents, it is more complicated), how much has the condo appreciated over the last 3 years since you bought it, and what would you do with the money when you sold?

EDUCATE YOURSELF - yes, it will take time, but will lead to a selection that better meets your expectations & avoids potentially costly surprises!

Thirty years ago, it cost me $600 in labor and parts to replace a 50-gallon hot water tank, currently $1,500 and often they only last 6 to 8 years. 

Selling costs time and money. 

You could promise a certain amount of closing costs then take a few grand off at closing.

If it was useable before (small ding) and is now destroyed, I'd take her up on her offer, but I'd also pay some of the costs as it wasn't new when she moved in. 

Very straight forward to use and cost effective.

It takes a ton of money invested to make up for a $35k startup cost.