Just follow the regular oil and filter change (at least at 4000 kms), fuel filter once a year (very cheap – Vic or Bosch replacement at less than P200) with regular air filter clean-up (atleast every month) and you will be fine. Very fuel efficient with an average of 10 + kms/li within city streets.

About the fog lamps, make sure that the lens / reflector are clean enough – kung hindi nabaha or whatever, otherwise any stock new or higher wattage bulb will be useless.

Check the existing isuzu highlander / crosswind threads for more tips and answers.