All too common an error this.
Don't skimp on the PPL. It really is like skimping on the house foundations. Its risky and can cost a LOT of money to put right later in your training career. A failed IRT can cost you a couple of grand in the blink of an eye.
If anything I'd go for a premium PPL course and skimp on IR stages if you're going to skimp anywhere. There's more to skimp on and if you're competent the basic course is enough to pass the test every time.
I used to teach 3 week PPL courses at what was the cheapest school in the whole country (cheaper than Florida after the air fare). It could *just* be done if everything aligned perfectly and the guy was good. But he would be exhausted at the end of it and usually a few years down the track would regret that they didn't take more time so as to enjoy the journey.
If you can, as I always advise, do your PPL at a decent school, not too far from home which also does CPL/IMC/MultiIR courses. This will make their investment in you from scratch so much higher that in nearly every case you'll get a much better overall standard of training. When I instructed in Jerez it was possible to have the same instructor from Effects of Controls 1 right through to your IR and that was A Very Good Thing.
A hastily taught, intensively learned PPL in a foreign country delivered by a mix of instructors is really really far from ideal. A good thorough PPL course taught by basically one guy in the same environment that you'll eventually tackle your CPL and IR in is much much more ideal.
That said, you're looking at a well trod path, it works but be sensible and as a minimum:
Don't treat it as a holiday,
Allow an extra week,
Allow an extra £500.
Good luck,
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