Old dog...

[Rabbit]

I tend to think Sara would do fine in your home if you were interested in her. While I am sure she has her habits that she would greatly miss, she probably would enjoy the attention and affection you would give her. Based solely on the fact that her current owner is willing to give her up (and not knowing more about the situation than that), it seems likely that she isn't getting as much attention and affection from her owner these days as she had grown accustomed to in the past and she would probably respond very well to someone who would appreciate her with fresh eyes.

I agree with Steel God in that you should decide what works best for yourself. I know far too many people who think nothing of passing along their pets like commodities as soon as they no longer fit their owner's changing lifestyles. I might pose the scenario to you whether you'd be happy adopting Sara knowing your friend would get a puppy six months later. If so, then I think it would be better for both you and Sara for you to adopt her from him. If not, then it's probably best you didn't.

Best of luck in whatever you decide,
Bill