His super cute, I would pay $200 if she would let me take him to the vet to make sure his in good health. As far as fleas I would give him Capstar to get rid of them ASAP and don't take any of his bed or blankies.
If you don't get him he will eventually end up on a shelter or the side of the road. Please try talking to her.
$500 is too much but $200 will atleast cover the neauter part in her defense. His super cute
JMHO