Monero by default, multisig built in, three live mirrors that the prober checks every ten minutes.
2-of-3 multisig escrow. Two-factor login. Verified mirrors. XMR by default. Vendor escrow. Active dispute panel.
Primary mirror handles the bulk of buyer traffic. Backups absorb spillover. Copy the Primary first; switch to a backup only if the challenge layer times out on your circuit.