but, it can be done, Anneke and CWolf know a lot more than i did about bringing home a retired racer,
however, i brought home a dog who had never much seen a human, spent his whole life in cage, 24/7, had been beaten, etc,
and he is a great pet! Yes, it did take him a while to get the hang of being inside of a house, he spent first 3 days staring at and behind the tv set (imagine a dog who had never seen a tv set?) and we had to turn it off so he'd stop looking behind it to find the source of the noises.
He was much like a lil alien who had just arrived on earth, evvvvvvvverything was brand new to HIM, although, he was an adult dog, he'd seen nothing but the inside of a cage in a dark barn his entire life, not even let out to pee or poop, not ever.
He is perfect lil dog now, really, the best behaved dog we've ever ever had ever, (except he is dog-aggressive, but, most of the other dogs rescued from that puppymill were not dog-aggressive, and most of the others all turned out just fine, once they got a chance to be loved).
so, even if your dog IS a hot mess, dogs can adjust pretty well, if anyone just gives them a chance. (the exceptions are the inborn aggressive dogs, but, if the dog you are looking to adopt *is* aggressive, it'll show by now, you'd hear about it, or see it yourself.) Feel free to ask them about any issues the dog may have, rescues tend to be very honest and up front on this, as they do want a good match, too.
i say, put up a fence, and go for it!! Write down all your questions so you don't forget to ask them, and do google "Bringing home an adult dog" (it's slightly different than bringing home a puppy) and go meet them!! or google, "bringing home a rescue" or "adopting a retired greyhound" etc etc, there is a ton of info on the net to help you learn what to expect,
and what are best moves you can do to help make the transition easier for you both.