Hi,
I would like create a 2of3 multisig address for receive a bitcoin payment and I went on https://coinb.in/
I'm the seller, one of the 3 users (the others are escrow service and buyer).

When I enter the 3 public keys on the multisig page and clic submit, it appears the multisig address (starts with 3) and the redeem script.
But if the buyer send the bitcoins to this multisig address, and I (or the escrow service) sign the transaction too, how can I receive the bitcoins?

How can I own the multisig address to receive the funds? I don't understand this.
Thank you very much