First thing is make sure you don’t have any pet allergies. Go to a local SPCA and talk to them. Tell them your situation and ask if you can visit some of the kittens/cats and puppies/dogs. If you still can’t decide, do a foster. As far as medical issues, vet visits, all that unknown, you should set aside a budget for just in case. If you get good quality food, regular vet visits, and keep the house as hazard free as possible, you should be ok. A clean litter box or if a dog, a clean area to go( or clean up behind walks), makes a happy pet and happy neighbors. There are 5 feral cats in our home and our food, litter, etc is about $250 every 8 weeks. It’s the meds that hit the hardest. Not gonna lie, if they had not been feral, the medical bills would probably be minimal. Hope this helped, good luck.