Deal review and advice needed

[Rick Baggenstoss]

I've agreed to buy a tired landlord's property.  He owns it outright.

We've agreed to $85k due in 3.5 years

$3k at closing

$700/mo interest only payments starting Jan, 2015

I plan to fix/flip the house this year for $25k in repairs and retail for ~$150K.  After the sale, I would like to hold on to the money for other projects until the due date in Jan, 2018.

How would you paper this? 

Thanks for the help.  

Rick