Repacing a cell phone cheaply

After my wife’s cell phone broke we went to the ATT cell phone store and bought the cheapest cell phone they had. With no upgrades or special deals it was $90 for a very basic phone. When my son’s phone died we went to Best Buy and bought an ATT pay as you go phone for $20, put the SIM card in it and use it like any other phone on our family plan. Phones are similar in quality and features, one just cost a lot less. Only works if you are on a provider that uses SIM cards like ATT. Thought some might find this information useful.