The logistics of them signing and sealing a permit from that distance may be a little rough, but they might know people local. 

Im thinking maybe it could be buffed out then sealed again?

Is it still being done by direct mail, bandit signs, cold calling to get the phone ringing with possible seals?

But, they stressed the  caveat that they do require more preventative maintenance: caulking, painting, sealing, termite treatment, etc.

If he or she is suggesting to install the solar at the same time as the roof, this is wise to do, as the roof attachments can be sealed by certified roofer and the warranty should stay stay valid.

Ultimately it may be in your best interest to take care of it and may be required by law depending on the state.Rats don't squeeze in under a door, not a normal door at least, so I would first make sure that all outside cracks, crevices and holes are filled up, especially in a crawl space to prevent anymore from getting in.Then, again it really depends on the state laws, but after my due diligence is done sealing up the up the outside and inside of any places a rat could get in I would think about telling the tenant that they can buy rat traps or whatever they want to use to get rid of what's is inside and I will reimburse them the cost with a recipe, I would only do this if I felt comfortable with local laws otherwise I would just hire a pest control person to take care of it.

Theirs an exterior private entrance already but I don't want to seal the door for if I ever want to sell the house.

Each of the four units will have to be sealed and fire separated from the others.

Good idea to be proactive as well...install pipe insulation, seal cracks, install electrical heat tape to pipes, etc. 

They had major issues with lead times and hitting their deliveries which was annoying, but we have also experienced an issue with the large sliding window in our master bedroom (seems a seal exposure/draft issue) already within a year or so.So I won't be buying Crestline again, maybe not fair but that's my data point...