Well etiquette says that if the price is firm, it is firm. That doesn't mean that all sellers follow proper etiquette.
'OBO' simply means Or Best Offer, that's all. No relation with the asking price. Usually it is lower than the asking price, but it could be higher, depending on supply and demand.
'OBO' simply means Or Best Offer, that's all. No relation with the asking price. Usually it is lower than the asking price, but it could be higher, depending on supply and demand.