car purchase

SAM told me his low price on a car and I said yes I will pay you that no problem. he said me him later that day well he called me back about a hour later and said people is wanting to give me more money than what I told you so could you do that. I said no cause you told me a price and you agreed to it but he said I couldn't have it for what he told me that I could. wow what kind of business is this ebay or what. not very trusting person do dill with hope this whole place is not like that. would not do any buying off of this place again