I want to build one that is simple. I really like something like the brewboss where I an remove the element. I am thinking just a simple PID controller with a switch for the pump. I am wondering if anyone has a parts list of a cost effective solution one can do themselves. Like where can it get the COFI style filter and what pot would I buy to fit it etc? I would like to do 10 gallon batches and sometimes double IPA's would I need a 20 gallon pot then?