Looking at the cars that are turned into taxis may help you decide.
Taxi operators want cars that are practical, economical and
relatively easier to maintain. I assume that's what you want also
I would suggest a 1996 to 1998 Nissan Sentra 1.4L or 1.6L (series 3). Buying the M/T version would save you some cash or let you buy a more "younger" unit and avoid the potential headache & expense of an aging A/T that is starting to fail due to age.
You can potentially get a good deal by checking out Nissan Sentra Club forums where a member or two might be selling their cherished rides because of growing family needs, etc.
Try to look for 1996-98 Nissan Sentra Series 3 1.6L, preferably from first hand owners. Or look at Buy and Sell Magazine, Manila Bulletin Classified Ads Sunday edition. Arrange for a test drive in case you found one that suits your budget.