It varies - some buns have lived up to 15 years, but as a lot of buns are the result of bad breeders or accidental litters - genetically they may have heart/teeth problems that will stop them living as long or healthly.
If your bun is spayed & vaccinated, wormed & regularly checked for all the hazards - flystrike/injury/abscesses, you will be giving her the best chance
3ft isn't really big enough to keep a bun in. Rescues tend to recommend 5foot by 2ft two tier or 6foot by 2 foot two tier with a permanent attached run. Hutch & run needs to be foz proof
It's also important that bun can stand up on her back legs - so plenty of head room.
The best thing you could do would be to get her spayed & bond her with a neutered male bun (from a Rescue
, so she had company
Feed - their diets should mostly be hay. Introduce veg slowly & pellets are better than mix - they only need a few
Stick around on here, you'll learn tonnes - & wind up like me, with 15 buns
:lol:
