only if the belts are damaged or near end of their life. Else, you should not go for a unwanted expense. Belts, specially timing ones are important and not every mechanic can set them properly.
the main ones are Brake Fluid and Engine Oil. I use Shell 10W40 in my Cuore that is running with almost 1,36,000KMs on odo. Avoid using 20W50 as many mechanics suggest. If engine produces smoke or reduces oil, find the leak and fix that instead of opting for thicker oil.