This is my viewpoint - I live in the Philippines some of the year.
Yachts are very scarce - and mostly owned by foreigners. I do not think many (if any) are in the yacht hire business.... but you can hire a yacht for the day.
cost is 5,000 peso's for 8 hours ... But for long term... full day lets say 6,500 per day. $125 US.
But - no-one is going to trust you to bring the yacht back. So you would get at least 2 crew members. The countryside rate for them is 450 per person/peso/day .... So lets say for 500 they will stay onboard... That's another $20.
When you leave Subic/Carmen/Puerto Galera where will you go ... island hopping ?? Possible. I assumed you are bringing your own up-to-date charts
with you... because there will be none on-board.
As a foreigner you need to renew your visa every 30 days. That needs to be done in a major city.
And you want to work
on the yacht using the internet
- a nautical digital nomad - not a snowballs chance in hell. Totally impossible.
So for 2 months....
$ 20/day Crew
$ 10/day Fuel
$ 10/day Food
$ 10/day Help/assistance
So for 2 months $10k.
Sorry if that does not help - but that's what I estimate the costs to be.