The vast majority on gumtree will offer some form of extras but the key terms/etc i recognize include:
1. Reference to the masseuse being "friendly" or "open minded"
2. Reference to prices being "from" an amount.
3. The contact number has a revealing lingerie pic on whatsapp.
4. No reference is made to "no sexual activities on offer" in the add.
5. Reference to "no sexual services on offer" is followed by a smiley emoji.
6. Massage being described as "relaxing".
7. Reference to "satisfaction being guaranteed" by the masseuse.
8. The ad is limited to a brief sentence like "call me for massage service".
9. Any reference to the masseuse being oriental.
I could go on.....and on.....