They were quick to pay when repairs had to be done and their in-house adjusters were on point.  

They are certified members of InterNACHI and pride themselves on thorough inspections.

I'd love to hear about your experiences and see whether my expectations just needs to be adjusted.

Just because you don't make any money on them, doesn't mean you aren't responsible, along with the source of the actual plans, for any mistakes in the plans, or even any mistakes in construction from lack of info, misunderstanding, or just plain stupidity of the builder/user of the plans.The licensing agreement will have guidance on having plans adjusted for local code, reviewed by architect/engineer etc. 

Do i need to be certified or do some official thing to take in a tenant like that?

Quote from @Brandon Hutslar: My rule: if rent is late, it must be paid in certified funds.

I would also consult with a certified cost segregation specialist in terms of classifying other assets into their appropriate class lives.

Using the example above, a cost segregation study can only apply to $500,000.Option 2 (simplified method): Taxpayers can elect to treat the adjusted basis of the exchanged property as if it was disposed of at the time of the exchange.

we have a primary fixed loan plus an adjustable heloc.

I sent the landlord a letter with 23 pictures using certified mail with return receipt.