1996 Toyota Camry Brake noise problem

I have a 1996 Toyota Camry. Recently, when I press brake to slow down my car, FROM TIME TO TIME (NOT ALL THE TIME), I hear some squealing sound (not very loud) from my rear tire. I had never changed brake pad since I bought the car brand new in 1996, is this the reason for the noise or is it time to change for new pad?

If yes, roughly how much it will cost to change the pad? Any other assembly needs to be changed as well?

Thanks. The noise is most likely the wear indicator telling you it's time to replace the rear brake pads.

Prices vary with the shop, your region, and the type of service you request. A Toyota dealer may be the most expensive. Check your weekend newspaper for advertised specials from independent shops.