If something needs to be done you can have them arrange the time for it with the vendor. 

How utilities are billed to Tenants depends on several factors including previous lease arrangement and how utilities are metered in a building.

You could show the arrangement with the paperwork.

However, I have no idea how you address the self-management tax issue in this arrangement if its all owned by you.So, of course, consult with some qualified professionals for the structure that works for you.But, if you were asking about a portfolio loan, I think there has been a fair amount of responses here, but nothing directly if the properties need to be held in one LLC.  

But my question is, IF someone is actually occupying the mobile home, can I change the locks and the electricity over to my name, essentially locking out that person who will be technically "squatting" since the actual owner died awhile ago and I as the new owner don't have any contract/ lease/ rental agreement arrangements with?

However, you did arrange for yourself a pretty Raw Deal here by putting only yourself on the mortgage without asking for anything extra.

"Seller carry" can mean any seller financing arrangement, if they say Seller willing to carry, they mean the seller is willing to finance some or all of the deal. :)

Who arranges for delivery and meets the truck?

In 2021 when this was arranged, the tribe contacted me asking for my SSN so they could issue the 1099 for that year.

You'll figure it out, really depends on who you rent to, could be a good arrangement. :)