The area seems clean but definitely lower income.

Less to clean 😉 I say all of this to get to the point of, how would you guys go about asking someone if you could use their land to park your Tiny House?

You'll clean some garbage and you'll do a ton of grunt work.  

I had to clean up after the squatters and their dog nearly destroyed the property.

Jeff would likely know some in London.As far as using an out of town lawyer to sign docs, you can do that all through fax or docusign in most cases.Most lawyers will give you a tough time about answering questions and working with cleaning up drafts, as it is their business and they deal with tons of tire kickers.

I asked her to allow me to do open house but she says she'll have to clean the house etc. etc.

Not sure if I'm going to fix it up and sell retail, or get it cleaned out and sell it as is.  

Just like a regular loan they sent an appraiser to give a value "as is" and an ARV based on the improvements I told them I would do.

In other words making the impossible possible.Goal is to be  "retired" from the regular J.O.B. market within 5 years. 

(but looks like you would for first month)...so back to your situation, which is not clean, but check your state rules and verify without the signed lease, you reverted to the month to month, so I would really document and communicate the end of June move out date (like verbal plus a follow up more formal looking letter) and prepare for the move out then and the painters, etc to come in..