I have been investing in real estate for well over twenty years and can tell you there are a lot of ways to make money in real estate. 

Assuming that your taxes and insurance are around $500 and your mortgage was $1,000 per month - even if you got a rate around 7-7.5% and had no money down I do nto see this property cashflowing.

I see hard money lending as just part of the cost when doing these kinds of deals.

It cost us more money than we would have liked to have spent, but we were able to put a house on the market that we were proud of.

Invest your money in a better deal. 

This could potentially meet your financial needs by itself as well as provide start up money to do flips or purchase buy and holds

Consider financing options like hard money loans, or FHA loans for house hacking, and focus on areas with strong rental demand near the MA/NH border.

Selling it now vs renting, will give your dad more money and he won't have to worry about renters or cap gains. 

I would be less concerned about the cheapest money and more concerned about decent terms and execution.

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