here's my advice..
settle on $15/month extra. reason being, if you have a landlord that is not happy with you, you will not be happy living there. Heating costs ARE going up, and heating 6 snakes IS noticeable. Probably not $30/month though! Still, she probably feels like she's being had. If I were you, first I'd look for an apartment that IS up to code, but in the mean time, pay the $15 extra...or at least offer that.
1.0 Reverse Okeetee Corn, 0.1 Albino Snow Corn, 1.1 Irian Jaya Carpet Pythons