First of all, you are definitely thinking along the right lines by considering this stuff up front. Many people don't - they save the money to get their PPL, then they finish their course and realise that they're going to need more money to use the license they worked so hard to get. Hopefully by working all this out up front you won't be one of the many who fail to keep their licenses current.
Agree with everything which other posters have said already. In the UK, the cheapest way of flying is to fly a homebuilt aircraft. You don't have to build it yourself - many people build an aircraft, then sell shares in it to recover some of the costs. You get all the benefits of owning a share of an aircraft, but the aircraft you own will quite likely be more interesting, and use far less fuel, than the type of aircraft you will train on. You're able to do the maintenance yourself to reduce costs further still.
I have no idea what the home-building community in Thailand is like, or what the regulations are, but if you're looking for a cheap, fun way of using your license once you get it, then this would be worth looking into.
FFF
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