I'm amazed at the prices you are all paying for lessons. I take weekly lessons in the UK from a qualified and very experienced IDTA teacher for £12 for 30 minutes. This rate seems typical for this area for beginners/intermediate social dancers.
I'll be taking a Silver Medal test in ballroom in May, by which time I'll have taken about twenty lessons (although I danced as a complete novice for two years as well, but twenty years ago). I'll have spent £240 on lessons by then, and my teacher seems confident that I can progress to Gold Medal standard by December (about another £350).
Apart from that, we pay £5 a week (per couple) to attend a social dance/practice session on a weekday evening lating three hours, and I have the use of a sports hall for practice two hours a week for nothing, becasue I work at the location, and I use the hall at a quiet time when no one else wants it!
All in all, I'm getting very good value out of my hobby, I think!