I'm not sure on the costs yet since hindi pa ako nagcanvass. May one year mahigit na nagbabawas yung sa amin and i just keep adding water to the reservoir since the car is rarely used.

It's the same case, yung reservoir ang nagababawas. After we overhauled the radiator, the leak left was in the bypass hose area. I discovered it when i heard water dripping and sizzling/evaporating after parking one time and i confirmed it with a friend who also had a 1.4 JX before.
Most likely ipapagawa namin kay Jorge in Banawe (same shop as Jemson the electrician) as they can do the repair. For parts, we either get at Youngbros (Banawe) or Nisway (near Ligaya/Marcos hiway).