GS - Alpha
I was in the same boat a couple of years ago - one trial lesson and i was hooked.
If you have a couple of grand of spare cash instead of buying a block of lessons tuck it away in a decent high interest account, at the mo you should be able to get 6 - 7% and draw it out for each lesson.
In terms of number of lessons, ask about what is the norm. I only know of one person to pass in 45 hours - and their father was a CFI.
I understand the average is around the 65 - 70 hours mark ( though i stand corrected )
Best of luck