I want this to be acceptable long term if I keep this method of financing. 

In fact, I don't think you should charge ANYONE because it was YOU who accepted that the switch is located in a common area. 

The only slight red flag was that they only accepted payment via Venmo or wire transfer, but that's how I accepted payment when I was selling lead bundles, so I still thought it was worth a shot.

There are a lot of deals to be done with them if you can adapt to their process and accept they will be very slow. 

My humble advice to anyone attempting to do creative finance is:Creative finance is for experienced investors who have access to capital if anything goes wrong.Learn the lawsDon't use a contract "off the internet", laws vary by state and are also regulated on a federal levelLearn the financing techniques correctlyDon’t skip parts of the processDon’t ever do a “kitchen table” closingUse the proper deedAn attorney can help you with the legal work, but the rest you are on your ownYour guru will not bail you out“Investing” in someone else’s deal by providing a small 2nd loan so the “investor” can pay for “cash to the seller” and for “closing costs” so he can do the deal is a very bad planKnow what problems can ariseLearn the responses and solutions to problems before they are neededKnow everything there is to know about Title and what that meansKnow who a "protected class" individual isLearn the "back doors"Learn human natureUnderstand timelinesUnderstand regulation enforcement (some of these "mistakes" have a 10 year statue of limitations ( they can charge you 10 years AFTER you do the transaction) and carry hefty fines and possible imprisonmentThe court doesn't accept "I didn't know" for an answer"Know that the source of the lead plays a serious role in some states and federallyKnow how much of a "profit" pushes the boundaries to invite an investigationYou can be sued by the seller if you don’t do things correctlyYou are automatically at fault if an investigator or attorney or regulator gets involved.

Still can be very beneficial for a new investor but personally I think not as good as a service as they had with their exclusive listings where they had inspections already done, rent rolls available, and you can complete the entire offer/acceptance via their platform rather than being handed off to an agent. 

.* No calls accepted to review receipts: I have asked Jenny several times for the last 3+ weeks to get on a call to review the receipts and all of the items that are in the house, I have given her several deadlines to resolve the issue, she has never accepted any of my invitations to join any calls despite me pleading her to do so as my credit card payment is now due and has a 29.99% interest rate if not paid.I have found several people that were also affected with just 2 facebook posts.

The property itself should bring in revenue ( even if you choose not to live in one side) and generally a bank will accept a portion of that rental income into the calculation. 

You will want to consult with a lawyer.In regards to your last two questions here's some background on what makes a contract valid and enforceable:Offer: A promise to do or not do something within a certain time period Acceptance: A clear and direct statement that all terms and responsibilities are accepted Consideration: A legal and adequate inducement given in exchange for the promise Capacity: The parties to the contract must have the legal capacity and competency to contract Awareness: A party must be aware of the contract Legality: The contract must be legal in the jurisdiction it will be operating in***Not legal advice*** Steps I would take: -Review contract in detail to understand each counterparties responsibilities (if you are not aware)- Email a copy of the lease to each of the tenants listed on the lease and reiterate lease expectations for termination notice, rent payment etc. - If the lease was signed via Docusign (other esign may have same ability) - you can go to the envelope, go to history and view the IP addresses for each action taken.

No other methods of payment accepted, written into the lease.