Caught abandoned bunny need advice

The last few nights I've been seeing two black bunnies around my apartment. Clearly they lacked survival skills and I could easily approach them, meaning they were abandoned pets. Was able to catch one tonight in hopes of saving it and I'm quickly falling in love with the little bastard.

I am going to talk to someone at a pet clinic tomorrow and have it checked but I would like to get some additional input.

How hard it is to care for a bunny? How long of a life span should I expect? Best way to give it the happy hoppity life it deserves? When I capture his buddy should try to keep them together? And lastly what kind of cost would I be looking at in both money and time spent?

Thank you for any input you can provide. Honestly just can't believe someone would abandon this sweet little bunbun and give it a death sentence like that.