Hi rich,
Yes, the 150 hours does include your PPL training. Also, for license issue you need to have 200 hours total time (as well as a number of other requirements, such as the 300nm flight with 2 stops). Since the course is a minimum of 25 hours, you may want to build your hours to a little more than this.
There are lots of ways of building hours. Yes, you can rent at £100/hr. Or you could go to America/Canada/Australia/South Africa and rent much cheaper. For less than £1000 you can buy a share in a single-seater PFA aircraft which will cost you around £15/hr and £15/month, so you can build 100 hours in 3 months for significantly under £3000, and that's assuming you can't or don't want to sell your share when you finish (but you may have trouble getting insured on some of these aircraft if you don't have any tail-wheel time). Insurance is far easier to get on a two-seater aircraft - I fly my aircraft for around £35/hr, and £50/month.
You will probably want to do a 5-hour minimum night qualification (if you don't, you'll only have to do an extra 5 hours of night training for your CPL). Or an IMC rating. Maybe have a go at aerobatics. Ever fancied getting a tail-wheel checkout? Or a sea-plane checkout?
The most important thing is to make use of your hour-building. Don't just spend 100 hours in the circuit. When you start your CPL course, you'll be expected to fly very accurate cross-country legs, and to be able to land consistently. Don't just build hours, make sure you gain experience and competence while you're at it. And, on that subject, you'll need to spend some time doing either the CPL exams or the ATPL exams before you start your CPL course. You might like to leave at least part of the hour-building until after your exams, so that you're current when you start the flying course.
Whatever you do, though, make it fun!
FFF
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