There are a lot of minor issues that aren't as urgent, but the main problem is the flat roof on the duplex most likely needs replacement.

Or is it just a flat 10%, as in if he lends you $100K, you pay him back $110K over the two years?

Wish I had the market you guys have, things are pretty flat here. 

I originally thought this area would stay pretty flat during increases and when the market falls. 

You're already in a much better place than 99.9% of beginners, having already purchased a 4-flat.

What if the price does not drop, and going up gradually or stay flat the next 3 years? 

.- We prefer washable paint to flat for rentals.  

I was thinking about having a room in the basement of our 5 plex with a washer and dryer. We would have a lock on the door and charge a monthly fee of maybe 30.00 so that a tenant will have a key to the room. Is this ...

We focused her energies and studies on what she loved and she was able to bypass math altogether in college and focus on English and History. 

Pre-Payment Penalty: If they have one, is it a flat penalty or does it have step down component like 6% of loan amount if paid off in year 1 / 5% if paid of in year 2 / 4% if paid off in year 3 / 3% if paid off in year 4 or is there a loan yield maintenance fee if paid off early Use of Funds: What are the funds being used for?