I had a huge number of lessons spaced out over a couple years, problems with time and money constraints meant I had a few long ish breaks and had to start back a bit from where I had got to each time. Anyway by the end of this I could get used to different car (I drove a total of 6 before i passed) in around 45minutes if that, and going to 3 different instructors gave me a pretty varied experience of the different ideas going around, surprising how different everyones opinions and methods of teaching are.
Anyway my main point was the best thing I ever did for learning was buy my own car, insure it (it's actually cheap as a learner just because there's always someone in the car with you, you're all labelled up with the overtake me plates etc) and start driving whenever me/my parents needed to go somewhere. By this time I had had a few lessons, but for the cost of 8 2 hour lessons i had unlimited driving time for petrol money, bargain! (yes my car was under £250

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I would say have a few lessons, get used to driving and make sure you know what you're doing, as I was quite often correcting my parents on lane discipline and the highway code

and then find your own car, you're going to buy one eventually anyway so why not get your moneys worth !
It's good to drive a few different cars as well, as some instructors will teach you a one car technique for doing certain manoeuvres whereas it's far better to learn how to do it properly. My last instructor did this and I passed my test doing a reverse park and reverse around a corner for the first time in my own car, parents were usually busy so were fine with a drive there and back in my car but not sitting around for an hour or so while i practiced manoeuvres.
Think there should probably be a prize for getting through that wall of text