depend on where you change... go high end place, sure charge you more

i send my casio back to macro to change batt and replace seal

any casios... as they are the distributor.

Cant recall price, but its very reasonable, better then go change at shopping center like sg wang/BTS.
Change original strap used to be RM45-80... where if you send to shop that sell watches, they also send back to Macro and then charge you RM100-200. That is how I find out about Macro. Change seal and you can go swimming without worrying about water going in your gshock as seal deteriorate after few years.

usually 5-10 minutes but can be 30 minutes wait if fella in front got 5-6 watch to change/repair... depend on got other people there or not. got couch and some old magazines to read if you dont have games on phone. Parking is shit at that area now, park in the old shops 10 minutes walk away and run across the big multilane road.