Why does it cost money to send a bitcoin transaction?
The BRD wallet does not charge any fees to send a transaction. However, the bitcoin network does require a fee, called a "transaction fee". This fee is calculated based on the amount of activity in your wallet, and is always displayed to you before you authorize a payment to be sent.
Wallets that receive many small payments before trying to send one large transaction may be charged a higher transaction fee. If possible, combining the payments you receive into a smaller number of larger transactions can keep your transaction fees low.