I also called the local manufactured housing association without success. 

Manufactured home located in desireable Northern California Subdivision of 205homes and city lots.

Am I able to do typically financing with mobile, or a manufactured home in a mobile home park?

Call another HVAC company in the area and perhaps they can do the warranty work for the manufacturer.   

If you are considering an prefab ADU, take a look at the prefab options with Back Porch Homes, they are prefab stick built homes and all materials used can be replaced/repaired with products you can find at your favorite hardware store instead of specialty stores like more manufactured homes.

If you look at the manufacturer recommendation they wont guarantee some of this equipment after a specific age, that released them from liability, the insurance will flag some of this items because of the age as well and they can exclude or prorate coverage.

We've been working with any/all lenders for 30 years on lot/parcel resident owned manufactured home projects and I don't know of any that will lend on a MH that's been moved from its original situs.

Currently the national debt to GDP level is the highest it’s been since WW2, which likely points to increased taxes (much higher than todays levels) and manufactured inflation in the future.

I can repair it with a sort of patch system but it will not be exactly the same due to the separate manufacturing of the laminate that is in place and the laminate patch.Do I have the right as the landlord to have the tenant pay for a whole new countertop or just a repair job that may not quite be back to original?

You just can't make this stuff up.I helped a client buy a manufactured home about 6 months ago.