Good morning! I would use a marketplace that keeps ownership with you, documents the lease clearly, and has a defined process for abuse reports and termination. InterLIR https://interlir.com/ works with IPv4 owners, buyers, and renters, helping you monetize unused space without selling it. You should ask how tenants are screened, who maintains route and RIR records, when payouts are made, and how quickly a problematic customer can be disconnected. Make sure the agreement limits permitted use, requires current contact data, and explains return of the block. Start with a shorter term until the workflow proves reliable.