I have allergies and it goes a long way to improving the indoor air quality.  

Not much to add here besides pointing out the indoor air quality (IAQ) makes a HUGE difference in quality of life.

Indoor pics show the need for extensive updating.  

I would never allow cats, in they pee indoors it can wreck more than a dog doing the same.I would not hesitate to rent to someone with two dogs, if I meet and photograph the dogs and get extra rent (we also go $25/month each) and a higher deposit.  

He has been misusing our pool (indoor) and he cause mold - we had the issue fixed 2 times and sealed to prevent problems - I think he is going to try to claim health issues also. 

makes a great point about mice / pets,, dry pet food is prime mouse buffet,, if it's an outdoor pet, or indoor the mice love it..

As you stated, it is natural that mice come indoors in the autumn/winter.   

Assuming it's going to need an indoor tank, I'm trying to figure out what to charge as a pet fee and/or extra deposit. 

You'll be surprised.I really don't care about weed unless they're smoking up indoors with no pecautions and it stinks, that's part of the smoming provision.

Heating costs go up in winter, as does electric due to the reduced natural light and people being indoors more.