My objective is for both parties to be treated fairly so that we can grow our partnership with mutual benefit for years to come. 

If you are reframing everything, might as well do it correctly and run your double joists from party wall to party wall, properly hang your headers on the double joists, and sister/replace the remaining joists.

If he changes insurance the lender will be notified and possibly call the loan.It does have a line in leases that lessor has the right to give 90 day notice if home is sold, at which time lessee must acknowledge and be out in 90 days unless agreement by new owner waives this right's well as a line if any legal action be brought by either party the prevailing party shall be reimbursed for all attorney fees and costs. 

A landlord may say, "not my problem", but in some circumstances the IRS can collect taxes from you or fine you if the receiving party didn't pay them. 

How should I structure contracts with lenders in order to keep it fair for all parties involved?

Go to the casino and watch roulette.

Title companies are independent third parties.

The party never ends! 

It's hard to believe we let people like this walk free.
New York Post : NYC tenant accused of turning pad into nightclub finally moves out.
https://nypost.com/2021/06/02/nyc-tenant-accused-of-turning-pad-into-nightc...

If so, that'd be great and I'll need to contact them to set it up.I'm not sure about FCI, but many servicers use a 3rd party like Corelogic, Lareta, NRTT, etc to track taxes.