The Castler digital escrow system is a platform that facilitates secure transactions between two parties by holding funds in a third-party account until the terms of the transaction are met. The fees associated with the escrow account are typically set by the platform and may vary depending on the size and complexity of the transaction. However, it may be possible to negotiate the fees associated with the escrow account with the platform or the other party involved in the transaction. This negotiation may depend on various factors such as the size of the transaction, the level of risk involved, and the terms of the agreement. It is important to note that negotiating the fees associated with the escrow account may not always be possible, and it is essential to understand the terms and conditions of the platform before engaging in any transaction.