My biggest tip is SEARCH EVERYONE, especially on LL.
And don't go texting/emailing SPs asking them if they're a scam, how recent their photos are, if you can bypass their screening/deposit protocol entirely, or if they can Facetime to "verify". You can find more about them by checking their ads, website, and searching their name here. If you are not satisfied, you can either book in and take the risk, or move on. I recommend the latter. Many reputable SPs work hard to set things up to show you they're legit before first contact.
Format for searching is FIRSTNAME ####, the # being last four digits of their work phone number. Some SPs do not post their phone numbers, so mine would just be my full work name 😇