Tico was 18 months to 2 years old when I caught him. He is 6 or 6 and a half now.
BTW, I also used to have 4 pet milk snakes and a lizard. I had three cats then (three different cats--it was quite a while ago). I never had a problem keeping them separate.
If you adopt them, don't just leave them outside when you go out of town. Have someone come in to feed them, water them and clean their litterbox.
You can use Revolution to clear up any fleas if they have them. It goes on their skin once a month. Talk to a vet about it.
My Tango is a fully indoor cat, as my other 2 female cats are, but Tico was too old to tolerate 100% indoor life when I adopted him, so as long as I am home I let him out one or two hours a day if the weather is clear. He stays close to home and comes when I clap for him to come in.
But when I must leave town, I hire a friend to feed and water my cats and clean their litterbox. Tico has to stay inside then, because I don't think he would come back in for anyone else who called for him.
Of course, I don't stay away for long--just 3 days and 2 nights over the weekend.
On Edit: My two former ferals were immediately affectionate with me. No taming required, but shy with outsiders, though Tico will warm up if he sees someone often enough.