Creating a finish any where near as durable as the factory paint is very difficult. Any home paint job you give it will be prone to chipping from the first day the bike is used. Often you will have paint damage resulting from minor bumps with tools when assembling the bike.

If you want the bike to look perfect, then you have to either pay for a professional refinishing from a reputable frame painter or a powdercoater, or get a new frame.

Also, leave negative feedback, and possibly file a report with ebay. The seller has the responsibility to accurately describe the item being sold. If he said 'looks new' a reasonable person would assume the whole thing looks new, even if he only intended to say the components look new.