Now, if you could get him to sell you the house, after which you could sell as a principal—that is legal.

If you invest everything in purchasing note, how will you pay legal fees, taxes, etc if you have to foreclose?

Worst case is you get nothing.I'm not a lawyer and this is not legal advice, but here are some reactions to what you stated in your post:If you can prove you actually paid the yard guy, and the landlord can't prove he did, you have a good argument on that line item. 

or assigns" wording may make it legal, but for a seller who doesn't understand, does that make it right?

Idk about the legalities there so I'm going to suggest an attorney.

"A Trust name is not party to a contract, it is not a legal person as a corporation is.

Even making a rock-bottom offer doesn't sit well with me sight unseen.This is in Iowa, but I am wondering if anyone knows the legal rights I would have if an offer were accepted with these tenants already in place?

I’m going to be moving out of state and want to keep my property but I’m unsure on all the changes that need to be done before it’s legally ready to rent out i.e home insurance, declaring to the state, etc.

I've told her I will help her with any legal fees as long as I can have assurance that she will sell the property to me once everything is cleared up. 

For example if I wanted to run an ad looking for potential sellers would I run into any legal trouble without a license?