Having someone with some skin in the game has been a good option. 

@Beth Cannon I would advise against offering a full month of rent free because you want tenants to have more skin in the game than just a deposit.

Would this be a good time to seek that out private money for 12-15% with as much skin in the game as I have, or would it better to seek out conventional financing after the single family is complete?      

At 20% down, that's your skin in the game, IMO a motivated seller should be accepting that.

But there are many ways to skin a cat and everyone's situation is different.

I'm a conservative investor, so when I invest in most real estate asset classes I prefer sponsors that have at least one full real-estate cycle of experience, little to no money lost, low leverage, and high skin in the game.And there is an apartment operator that has multiple real estate cycles of experience (decades) with no money lost, low 65% less LTV, and high 10%+ skin in the game.

No skin in the game.

My plan is to "wholesale a mhp," so that I can have some "skin in the game," as it were, for buying my first park. 

The downside is they will only go 50% LTV so you would have to have a lot of skin in property. 

However, you can make money managing properties without any skin in the game.