Your property is similar to mine in great Indianapolis suburb with good schools owned since 2013 - worth about $300,000 (possibly could get a little more if in a multiple offer situation), property tax $6249.

Check out investor lift, there are sometimes good deals on there, but make sure you vet the area and try to get a due diligence period on your offer, a lot of the times you can trust their ARV or their take on the condition of the home.

It had been listed almost a year when we made an offer.

To help avoid a lot of these issues I would think about buying a "Modular" or use a "Tiny Home" vendor who offer these in many states.

I put 20% (54,000) and then an additional 7% of the loan amount ($15,000) since the bank only offered 93% loan of the purchase price. 

It offers a modern look, makes spaces feel bigger, and is easy to clean.

Other good strategies, are targeting tired landlords (absentee, owned 10+ years) or drive around and find distressed properties, and call the owner from the records you find on TruePeopleSearch.comAnother method if you want to stay on market would be to send offers that are well under asking price for properties listed 60 days or more.  

The owner didn't have to deal with any of it, as we offered to take care of it for her.

Also, often times the original homeowners still live in the property so once the sale is ratified you have to go through the eviction process or offer cash for keys to get them to leave.

Your son is likely paying more than the property is worth, by definition, as the seller would almost certainly prefer a similar offer that was not subject to.