1. Reverse image search of pics--you can just drag and drop into google images from rentmen.eu. If it leads to instagram or twitter or onlyfans, etc., check what's visible at those sites.
2. Google his phone number and do a search for his phone number at Facebook.
3. Check the rentmen reviews--look at the number and timing sequence compared to when the ad appeared, check the text comments using hide.me, and research the reviewers using their screenname, also check for any comments about the reviewers here (a few are notorious).
4. See if there's anything at daddysreviews.
5. Search here, if no info, then do a 411.
6. PM/DM anyone who mentions personal experience.
7. Make contact through rentmen im and see how the communications go. Can proceed to texting with the provider, especially if he declines to communicate with rentmen im.
8. If you're still hesitant but hopeful, try to make the first meeting at a neutral site before you go to his/your place. Some providers will agree, many will not.