For most countries they will automatically give you a 30 day visa on arrival, but if you plan to stay in the Philippines longer, I would suggest you get a 30 day extension on arrival (because it can be expensive and timely to get to the visa extension place). Otherwise, once in country, you can easily get extensions, but only in certain places. Such as Manila and Cebu (where you can also get 6 month extensions), or Puerto Princesa (not far from the airport) in Palawan, but where you can only get a maximum of 2 months extension every time.
I found the pricing a bit strange, as it seems to vary depending on which extension. The first one can be the most expensive (per month) and should be a maximum of 30 days. After that you can get 2 or 6 month extensions. I am currently paying about 8,000p for a six month extension, through the following agency (they can also arrange domestic and international ticketing for you):
Which is great, because I can leave them my passport and do not have to leave my beautiful island every six months, the cost of which (including getting back and staying at least one night in Manila) can easily cost as much as the extension itself.
Live in paradise, don’t have to leave, except once every three years and it need only be for a very brief time (out-in). But hey, while doing so, might as well explore some of the nearby countries before heading back. I love the ease with which I can stay in this country.
Back to our suggested itinerary for the Palawan area.