Pier and Beam foundation for 1 1/2 story cottage.

[john13713]

I can use a little guidance, this is my first build and the land I purchased is in Central Texas. It has a lot of this Black expansive clay soil. I was looking in to using the Diamond pier footings that use pins driven into the ground or the Bigfoot footings that are actual concrete piers. Looking for suggestions on both..... Also if i use the Bigfoot Footing, How far should i place them into the ground? My frost line is only 5-10". But how far would I need to go to make these really stable? I am on unrestricted land and there is no code enforcement. THANKS!