The owner gave permission to go ahead and have a locksmith come out and change the locks but I am assuming the locksmith will want some form of proof of ownership.

Now, I am not completely opposed to allowing pets but tenants should have discussed this and got permission to have a pet probably I would have allowed with pet fee. 

The Permitting Procedure: Recognise the garage conversion permission process.

There are other websites that get a limited set of date from the MLS with the MLSes permission, but your are not really "accessing the MLS".  

They admitted that was dumb because it was basically giving company permission to give 0% raise.

This is just the most recent one, there's other pretty strict laws you might want to look up...Landlords cannot ask applicants if they’ve ever been convicted of a crime.Landlords cannot ask for permission to run a background check before a tenant is approved.Landlords cannot look at criminal history when they’re making their decisions.https://www.mynd.co/oaklands-f...

The unit is empty now and I was going to ask the selling agent for permission to use pictures just for advertising. 

I assume you're getting the landlord's permission to STR the space (I hope!)

If you get permission from the fellow investor and there is no copyright concern then you may use that form.

I'm starting with my first LTR, and I just received a PM contract that looks like it gives them a ton of permissions, but doesn't actually say what they promise to do.