the advice offered so far is sound. You shoulkd always go for the largest cap its lathe you can afford. There is nothing wrong with some of the small hobby market lathes from companies like Warco. These uasually come supplied with chucks etc and are quite capable. I have used one or two of them and I found they lack power and to do serious work took a lot more smaller cuts than would have needed on a larger lathe.
I have had a Myford 3 1/2" lathe in the past and they are a brilliant lathe though I found that for a lot of work I was doing I was pushing it to the limit in terms of capacity.
I would suggest a lathe with a centre height of 5"-7" might be ideal.