It's not difficult to recognise that the Forbes Park and Dasmarinas area is one of the wealthiest parts of the city. The villas are hidden beyond high walls, and thesideroads are gated-off to the public.
Along McKinley Road, you will come to along the Plaza San Antonio. This place is overlooked by the San Antonio Church - with its light-yellow painted exterior giving a relaxed athmosphere to the place, with remiscences to the spanish era - although the church was only built in the 1950s. On the opposite site you find a small shopping arcade with the usual coffee shop, a supermarket and restaurants.
Especially during the weekend this place is busy with muggles. There are often wedding ceremonies in the church.
Therefore the cache is not hidden directly at the given coordinates, which will lead you in front of the church. The box itself is a bit off from the main muggle stream. There is no need to enter the church area for answering the questions or finding the cache.
To calculate the coordinates, solve the following questions.
For North coordinates: Number of Bells visible in the Church Tower multiplied with the number of palm trees in the first row of the parking lot (towards the church). Add the number of windows in the church front, plus the number of windows in the church tower front. Deduct the result from the last 3 digits of the anchor coordinates. .
For East coordinates: add the result of the above calculation, plus the number of windows in the church front plus the number of windows in the church tower front to the last 3 digits of the anchor coordinates.
Note: the GPS signal can be weak resulting in low accuracy. Use the hint! Update 14.09.2015: Formla updated to local situation, no change in coordinates.