An IRA is an individual retirement arrangement, and quite permanent by nature. 

Are there any verbal agreements or arrangements between the current Landlord and Tenant?

Assuming you can not contact your tenant, which seems very strange, you arrange to have Animal Control present to remove the dog when you are ready to enter with your plumber.Usually what I would do is open the doors and let the animal lose.

I get why some sellers are desperate enough to cash in their chips for a discount, but not so much why they would accept lower monthly drip feed than they could arrange for themselves?

If the loan is through a specific company, can we go straight to them and arrange a mortgage that would include the remaining balance, plus the cost of repairs under one contract while also selling the house to us?

Also arrange a contact person for major repairs.

Anyone in area have any suggestions on a Property Management company who would be comfortable with such an arrangement?

Be creative on the deals you do and get it arranged in a way that you will enjoy it. 

In the United States, when credits are applied to a purchase price the agreement becomes a financing contract and these contracts have been identified as predatory lending arrangements under the Dodd-Frank Act.

I was planning on attending the meetup that @Jason Van Till was referring to, but unfortunately I wasn't able to re-arrange other family priorities.