Bitcoin payments are irreversible, so if you send first the scammer can simply not pay you and keep their bitcoins. One often wonders what determines the price of Bitcoin. Available on Coindirect. You can usually receive your bitcoins within a couple hours. Limits, however, will vary between individual sellers and are usually lower than online exchanges. In Bitcoin these wallets are not called an account but a wallet functions almost the same way. A physical bitcoin for sale.