@Nicolas Falbo Your title company/attorney will do that for you. If you don't have one yet, get some recommendations from other wholesalers, give them a call and have a brief chat and let them know "so and so big wholesaler" recommended them to you.
Send your signed purchase contract with you and the seller to the title co and ask them to run the title on it. They'll usually do it for you for free, because they'll get paid on the closing.
Key point: in your original purchase contract with the seller, always have the language that "BUYER PAYS ALL CLOSING COSTS". That means you, or in this case, your buyer after you assign the deal will pay for the closing costs.
Make sure they know that upfront, which is pretty standard with wholesale deals.
You as the wholesaler won't pay for any costs. You just make the middle spread between your contract purchase price with the seller and your assignment contract price with the buyer. Very clean. The title co will make sure you get paid at closing.
Just stay in good communication with all parties, incl title co, throughout the process