I think the clue to Tony's situation was in his first sentence when he mentioned it will be his first flight.
He has not travelled a long way out of the UK so his naivety is easy to understand as he hasn't had anyone he trusts to give him the basic facts he needs.
He has understood from his friends that the Philippines is not as rich as the UK, but they did not tell him how much money he will need when he gets there. They are probably encouraging him in his dreams, as he is marrying a friend's sister.
I just hope he is reading all of the replies in this thread and to not be put off by everyone's replies, but to see them as friendly advice. After all, we are mostly seasoned hands at this and a few of us are better travelled than most.
Tony, if you are reading this, do not think about marrying this lady until you have known her a while and have built up a lot of trust with her over time.
Take your time and just go and have fun the first visit.
Filipinas can capture your heart very easily, but you must temper your desires for the future with a dose of realism.
If you enjoy her company face-to-face and she is a sensible lady, she will understand your financial situation and will back you up with your joint dream.
You will need to build up "evidence of relationship" for her probable visa application, this takes time and everything needs to be documented and planned for.
Everything can be done, but in the right way and unfortunately it will be an expensive adventure.
So, don't go without £500 minimum and look for good solid work in the UK to fund your adventures.