I wish people would spay and neuter more than they do. I had a large colony (at least for me -- 30+) dumped on me when a neighbor died. She let them breed unchecked. She enjoyed them, fed them...and then she died. Her family's only effort with the colony was to make sure none of the cats were in the house when they locked it up, then drove off and left them to starve, which is where I stepped in. I cannot bear to see a hungry cat.
The younger ones were semi-sociable, and with a lot of work became quite sweet. The neighbor on the other side of this abandoned colony jumped in and was able to get quite a few of them adopted. Most were successes, but there were a few painful failures, including one who was let outside when the adopter specifically promised she would not, and the dear kitty made a run for our colony. She never made it back
I worked with a local cat rescue, and my neighbor had a great deal of success through PetFinder utilizing the cat rescue's adoption contract, which was just killer vicious in laying out what they would and would not do with this cat. She interviewed potential adopters and let them meet the cat in her home. It worked very well.
If you do follow this path, interview carefully. Remember, THEY want YOUR cat, so you ask the questions. Don't be afraid to say they aren't the family you want for your cat. If you are willing to take the cat back if it doesn't work out after a trial period, it will help prevent cat dumping or your cats winding up in shelters.
Our colony is now down to 3 cats that eat at the neighbor's house. About half were placed, 4 were killed by cars, and the rest eaten by coyotes, which is heartbreaking, but unpreventable. We celebrate those that have warm homes to curl up in on this cold New Year's Eve. You're doing a good thing for these cats; you have a wonderful, loving heart and they're lucky to have found you.