This means you can read the juicy details of your own reviews, you can use the TER PM system, and you can whitelist clients. If you desire full VIP, then you have to pay for it. (Or earn it via problem reports and RAPs, 2 days at a time)
Full VIP gives you the above Limited Provider VIP functions, plus you can read all reviews and you have access to more search functions. Some providers find full VIP beneficial for screening and other purposes.
However, VIP membership has nothing to do with posting ads. Your subject line asked how do you post ads, then inside your posts you asked about VIP. Two totally separate questions. You do not need VIP (Limited or full) to post ads on TER. All you need is a link to another internet presence, such as a personal website (which in turn would have to link back to TER), an ad on an approved ad mall, (EROS, cityvibe, slixa, myproviderguide, and many others. It can't be an ad on another review site) a profile on a verification site, (i.e. P411--yes I did see your other post. I know you are not on there yet, but when you do get on you can use that link) or even just a link back to your TER profile.
Look at the "TER Instruction Manual" (the thread at the top of the page) and read the "Provider Ad Posting Guidelines." The rules are not complicated but they are pretty specific, and you must follow them or your ad will not be allowed.
Good luck.
