Best book on hard and private money?!

[Samuel Fletcher Hardy]

Hey guys so I'm working on my second deal and it's my first exposure to private and hard money. I am looking for all the advice or book suggestions I can get!

The deal

It's a 1200sqft(total) triplex

2 of the units are 1bed 1baths

1 studio.

The rents are at $350 a monthish and the market is at $900 a month minimum each.

I think I can purchase it around the $120,000 mark it needs a full rehab I estimate it will take $65,000. I am a licensed contractor so I plan to get some sweat equity. ARV is a minimum of $300,000. I own a triplex a block away that just appraised for $375,000

I have started looking at hard money loans but dont quite understand how interest only works.

I am also talking with a private investor that is interested at a 10% interest rate on a 6 month note.

What questions am I needing to ask and missing?

Thanks in advance guys you guys rock!