I can either purchase the land for 150K+ rehab cost with hard money lender.Or pay what they owe (50K) and get a construction loan and pay them after I refinanced the ARV.

Over three decades, I've not seen a ton of situations where no money down/100% leverage has worked well. 

I ran into these gugys personally coming out of the GFC were money was really tough to raise..

Use the money only to stabilize assets and yourself.

Hi Jacob, There are DSCR and Hard Money Lenders that will finance a manufactured home as long as it is not in a rural area, and there is no land lease.

This is why huge nationally scoped/wall st back or securitized hard money lenders will have a hard time dominating the this very segmented market.

Is this reasonable or do I need more money?

thats basic list one can add.Value add /  New construction / land entitlements/ Timber / Minerals/ Lendingetc etc.. far more ways to actually make money than just buy and wait for rental income to payoff debtl 

The one thing I am unsure about is how earnest money works when you have yet to find a willing buyer to assign the contract to?

I would never put my money into a shrinking population base.