Hi Sonar - pleased you are coming and training with Divedojo.
Our experience of ATM's, banks, VISA;
We strongly suggest that you go to a bank in Manila which provides VISA/Mastercard/etc cash withdrawals while you are there. Banks with this facility allow you to withdraw 100,000 pesos (with 2xID) over the counter.
There is a small one-off fee for this. Additionally, bring US dollars which you can easily exchange (not travellers cheques which many don't understand what to do with).
Most credit card payments here carry a 6% min (tres expensive for us, from the US or - from Europe). Again, get what cash you can in pesos in Manila before you travel.
IMPORTANTLY: since the World banks screwed themselves and us nice people, we innocents are finding it harder (not easier) to get hold of our hard earned cash overseas. VISA, MSTERCARD et al are withdrawing their facilities due to excuses of 'fraud and corruption' in the PI's. In essence, this means it's harder to get cash here (e.g. - impossible in Davao to use your visa for cash advance now).
Manila offers you the best chance to get a good sum of pesos from a bank via cash advance.
You can use ATM's in most places no problem (HSBC lets you take up to your daily cash limit - to 40,000 pesos - most allow a 5,000 peso withdrawal (fee for each card use)).
Also note that it is very likely that your bank will ' freeze' withdrawals after the first use of your card here. Therefore, please ensure you pre-arrange with your bank that you are travelling here AND have a plan to call them/sort this out if your card gets frozen.
Though a bit of a pain, hope this is useful.