Potentially yes. After you have stayed here for a certain time (perhaps at least two months), you will need an NBI clearance before you leave. Basically you must go to some police branch where they confirm you have a clean record and perhaps owe no institutional debts. Make sure you check this out thoroughly before making the long and expensive trek to Manila!
Not really, just make sure you are prepared well in advance, so there are no last second surprises. Again, it depends on which country you are from and where you are applying, but if applying in the big centers like Manila or Cebu, you can easily get a six month extension, and keep repeating that until your stay in the country has reached three years. After which you need to at least cross the border briefly before starting the process all over again.
For a temporary visitor or tourist visa, the general minimum requirements are:
- Passport/Travel Document Valid for at least six (6) months beyond the intended period of stay in the Philippines;
- Duly Accomplished Visa application form;
- Proof of bona fide status as tourist or businessman;
- Confirmed tickets for return or onward journey to the next port of destination;
But again, this can vary depending on the country of your passport, so make sure to check with your embassy in Manila.
Depends on which country your passport is from, but generally often 90 days. Best is to consult your embassy in Manila or refer to the information above.