Looking for advice, any feedback helps

[Chala Kedir]

Hello, 

I'm looking for some guidance on if this is an okey invest or not. My Boss has offered to sell one of his property which is a single family home on a contract for deed. 

Here is the terms below 

Price - 350kDown Payment - 30kFinance 320k at 7% (interest only) for a monthly payment of $1866.67 a month
Current 30 year fixed rates are 7-7.5% and I would do interest only to keep the payment down
Property Taxes are currently $5488 (as a non homestead, so if you convert to homestead it will go down, just not sure exactly how much)
Insurance - I pay about $1200 a year (yours may be higher / lower as I have multiple properties)
Balloon - 2 years

The arv on zillow is anywhere between 327-360, Im going to counter at 335k, I don't plan on the property having any equity for the next few years as the property went from 260 last year to 300 in value. My goal would be to keep it for a longer period and one day use it as a group home. 

the property is a 5 bedroom 3bed unit about 2200 sq, its in a c class area, and rent is about 2100-2200. while a living in the property, I  would  rent the basement out which has a 1 bedroom and full bathroom could go from any were between 600-800. 

Any thoughts would be greatly appreciated.