However, this item (guitar) doesn't meet any of those circumstances. It was not 'loaned', it has nothing to do with retail establishments and was simply an item that was given to someone to help promote their product. There is NO evidence that it was a loan or cannot be sold or otherwise disposed of. Over the years, I have owned, sold and given away lots of 'promotional' crap.... including beer (Corona, Michelob, etc.) signs, coasters, mugs, golf balls, jackets, bottles of wine, etc.It is common practice in this industry for distributors of alcohol to "lend" promotional merchandise to its customers. Neon signs, pool tables, lights, reach in refrigerators, and other branded merchandise is to be used by these customers but not sold for profit. That merchandise is supposed to be returned upon termination of their working relationship. Since many of these working relationships go on for many years, much of the merchandise is forgotten about. The ownership however still remains with the distributor. It would be illegal for anyone to sell something that would fall under this category.
The OP has complete OWNERSHIP of the item and can sell or give away as he feels fit.