If you really like building your own equipment there is a good
set of instructions in Rock&Gem, November 1980, pp 8-15. These
instructions enable you to build a 600W Kiln with very minimal
outlay. I built one for myself and it works fine - especially
since I just plug it into wall-plug as it draws only 600 Watts
instead of the 1800 W that the commnercial kiln draw.
The cost may possibly be less the $50.00