The start of any successful negotiations is to know what you want as one party in the transaction. If you know what you want and don't get it then you walk. If you don't know what you want then you are in the same place before you knew someone was interested so toss a coin with heads you sell and tales you don't.

Also, most sellers way over estimate the value of their business. A business is only worth what someone will pay for it. It's value is generally modeled around cashflow or how much revenue it generates or what the owner gets to keep in their pocket. If you think your business is worth $35,000 then its not making much money and sounds more like a hobby. To help you decide whether or not to sell, do you have the heart to keep going for the long term or is it time to try something else.