Like a ricer, this is a souped-up car, combining the words chav and ferrari. Often has a large spoiler on the back, scary looking headlights and sometimes even coloured lights underneath the car. Oooh.
"Check out the massiveteatray on the back of that chaverrari"
A corruption of glitteratti, meaning the hoi poloi or high society. In this case it's the complete antithesis. The celebrity chav and their associates.
Usually used in association with rich and successful, by their own standards, chavs. EG. lower league footballers and the women who try to sleep with them or reality TV idiots. The chaveratti were out in force last night at Ritzys nightclub in Romford.