getting your car professionally waxed and polished is a 150$ endevour.
And I wouldn't let Ameteurs touch your car unless you've seen their work. 30$ is really cheap though. Bet he will leave you with more swirls and streaks than you started with lol
Imo detailing is a diy. If you love your car you will clean it yourself.
if you refuse to do it yourself, save some more cash because no detailer beyond amateurs will do it for only 50$. I'll do it for 120$!