There are ways to mitigate the costs and protect yourself to the extent possible.

My partner is a builder in the LA area and his client posed an interesting question for him that could affect financing in the future. 

Possibly one you have a relationship with. 

In real estate investing, financing is as important as finding the right property.

I use partnerships to help me fund my projects when it is hard to get financing.

The park will be a lot more tricky to finance 

Are you familiar with Creative Financing such as Subject To (SubTo), SubTail, WRAPS, Short Term Lending, and Bridge loans? 

I was looking to get some advice on the best way to finance a small mixed-use property?

I want to create a fund that will allow me to purchase distressed homes, fix them up, and sell with owner financing (possibly including a 5 year balloon so as to be able to recapitalize periodically and give investors a shorter horizon).

Quote from @Caleb Christopher: I use OnePoint Lending as the servicer for our seller finance and wraparound deals (www.onepointlending.com).