If you tell the franchisor this up front they won't approve the sale. As part of the sale there is likely a non-compete. So, if you do this after the fact they'll sue you and your 1st location. If you give the franchisor a boat load of money that is worth several years of franchisee fees, maybe it will fly. But then, why not just start your own 2nd location?

I'm of the belief that everything's negotiable. You would need to talk to the franchisor about your plans with this purchase. Others have mentioned the non-compete, and that will likely mean a 'No' from them but I don't know the circumstances this operator is going through. Would operating it as a franchise location be totally out of the question? You can look at p&l and arrive at a conclusion that works for you I'm sure.