Check your local laws to see if that is legal.

We're in Arizona if that makes any legal difference.

I'm fine with combing the market for deals, just trying to find a way to legally secure financing without a due on sale clause raining on my parade.

Unless there is significant equity in the property 50% LTV may not be enough to payoff the current underlying mortgage.Now here are the exceptions to lift the COB 50% limited LTV restriction:- you inherit the property and it was transferred into your name either via legal award from a domestic partnership/marriage - you have been on title for 24 + months- you took title to the property that was transferred from a partnership or partnership like entity (LLC, LP, etc) that you can document the ownership of 25% or more in- you lived in the property and have been on title for atleast 12 months as a primary residence- you have paid the mortgage for atleast 12 months - or you can demonstrate a relationship with the obligator (domestic partner, relative, family member, etc. )If you qualify for one of the exceptions you are not limited to the 50% max LTV  when considering fannie/freddie conventional cash out refinances on a subject to transaction.

In what ways can JVs be structured to finance a RE investment, and what are the main legal and financial considerations for parties entering into such agreements?

Because of the money involved with lost rents, we are now contemplating legal action along with our homeowner client. 

LLC is going to give you legal protection to some degree, but there is no difference from a tax perspective.

At the end of the day, the legal arrangement has changed, but the functional arrangement is basically the same.  

And your IRA/401k is a separate legal entity from you.

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