My 2 cents. I do this often and I always fly to Hong Kong, decompress for a night, and then press on. Once you are in Asia you can get a flight to MNL for under 300 bucks. Hotels can be expensive in HK but look at the Ibis Styles, or the Excelsior which has a fantastic location in Causeway Bay. Another good route into MNL is ANA thru Narita. Always try to get into Terminal 3 in Manila as getting out of T1 is a nightmare. I would also suggest you stay in Makati City in Manila as its the only safe region in the city. In Makati you can walk out on the street in relative safety and you can trust the tourist police, if you stay out near the airport in Pasay you can not trust the police. Again, do not trust the police anywhere outside of Makati.
I also suggest you look at adding on a few days in Puerto Galera (Sabang/Little Laguna) as you can get there from the Batangas Pier T3 and the diving is deeper and more diverse than in Anilao. If you are going to haul all the way over you should take advantage of being there.
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