Not sure where you're based but in the UK BoughtByMany used to do a fixed for life policy - monthly premium fixed for life, guaranteed, regardless of claims - but sadly they discontinued it in December apparently due to lack of interest (I know because I'd just recommended it to someone at the...
Kittens often get a bit of stomach upset when moving to a new home - stress and changes in diet etc. This looks within the range of normalish to me, reasonable colour (i.e brown, not black or white or green or with any blood, etc) just a bit squishy, but please note I'm not a vet, just a kitten...
It certainly looks very bruised to me and the incision looks more open than I'd have expected :( Is she an adult cat or a kitten?
We've just had our two (4 and 5 month old) kittens spayed and I'd note neither of their incisions looked like that - but they're also both very young and healed...