Thanks for the advice @Erin Margaret and @Mike Hanneman. I did a little digging in the PVA files and found out that the last appraisal was 10 years ago and the house appraised for $45,000. At that time it was a SF residence with a detached garage. A bathroom was added and the garage was converted to an efficiency apartment. It was sold to the current owner two years ago for $85,000. I'm not 100% sure that the addition of the garage apartment was approved by the planning commission as the taxable value of the house and lot didn't change even with the increase in recorded sale price.
@Erin Margaret, I don't have an insurance quote yet but have an agent I've known for years working on one for me. This part of the city got new sidewalks four years ago when it got a new elementary school and the roads in this area are not included in the five year overlay plan, so i should be ok on than. The house comes with a lawn-mower and the current tenants seem to keep on top of upkeep, at least for now. I budgeted about $1,000 for annual repairs, and have the skills to take care of everything with the exception of electrical or major plumbing. The tax bill, if the house is appraised at 85,000 would be about $290.
I don't really like the idea of having a balloon payment and need to see if the owner is interested in selling outright. I'm working on setting up a meeting with a local lender who contacted me through BP a few days ago, so hopefully he will have some ideas on a good way to move forward.