Talk to the staff at the rescue centre, an older dog may be more suitable but in the end I think heart rules head. Before we got our last rescue dog we looked at several on the website, not too big a dog as one of mine recently pulled me over. Be honest about what you have to offer in the way of time, garden, experience etc. Our little girl is the kindest, gentlest little dog despite being very badly treated by a previous owner. Previous ill treatment does not necessarily mean the dog will have problems. Good luck, we have so much love and pleasure from our dogs.