What I would change if I could do it over again - and making sure I had a good, profitable business up and running before putting my roots down in a particular place.
In my experience a lot of foreigners run into many unexpected costs once they decide to set up a permanent abode in the Philippines... and like others have said it is more expensive to live here than most people think. Exchange rates can change, either in our favour or otherwise, and the price of everything here seems to keep going up and up. So if a foreigner is buying a car, house and business and everything costs more than they expected, they can end up with very little savings in the end. This is why it's good to have a plan to get out if you need to.
The notion of having a business, while attractive at first blush, is not for everyone. It brings to mind the old saying: "How do you make a small fortune in the Philippines? Start with a large one."
There does seem to be a common line of thought with foreigners coming to the RP that starting a business is a piece of cake. And that is from folks who never owned and operated a business in their home country. Yet they think they can do it in the Phils, a foreign land, language and culture. Not sure what leads to that thinking.
To me, the best advice is not to in any way depend on making money in the Phils. You should have your financial house in order before you come and have reliable offshore sources of income. In that case, if you have some capital you can afford to lose, then indulge, if you will, in a starting a business and, if it makes money, regard it as gravy and if it fails, no big deal.
For those of use who happen to be the sole or principal source of support for our spouses, I think it also of fundamental importance to provide for them when we are gone. Even with couples the same age, one can easily outlive the other by a fair margin. So, if you are the provider and you have pension income supporting both of you (and any anak), then make sure there is an adequate survivor benefit or have some other bullet-proof revenue source that will take care of those you leave behind. I have heard some kanos say; "Well, I bought a house and she'll have that when I'm gone." Really? You expect your spouse to have to sell her home in order to survive? Moreover, property in the Phils can be a hard sell, the money it brings will not likely last and allow a comfortable lifestyle, and that is drawing a long bow and assuming your spouse has the ability to providently manage a large capital sum. For my own part, my asawa is mid-30s, of modest education and fiscal experience. She's smart in many ways. Yet I know to a certainty that if I passed tomorrow and left her $1million (P50 million), the money would be long gone before she reached old age.
I'll add to this post that I find myself in respectful agreement with HappyBee's comment about living costs in the PI being much higher than some foreigners expect. It is trite lore that if you move to the PI and think you can live as you did back in the U.S., the U.K., Australia or wherever, but at less cost, you will be disappointed. One still encounters online comments such as "live like a king in the Phils for $500 or $1,000 per month." B.S. That translates to: "Move to the PI, go native and survive on $1,000 per month." And don't get sick.
I lament that the old Asawa Forum has lapsed into history lo these many years ago. For awhile, the old posts were still available online. No more. There, one learned and experienced member once started a thread sub nom. "Marooned". It was a sobering tale of those who have moved to the Phils expecting to live the high life at modest cost and found themselves after a few years with not even sufficient funds to buy a ticket back home. I have witnessed a few marooned types in the Phils myself. Pitiful. To one such fellow I "loaned" USD550 to help him buy a ticket out. He's now in his 60s, working as a pizza delivery driver when he can, in LA. Don't end up like that.