I would get in touch with schaez and see if he would be willing to give you some guidance. I was in three previous group buys (different name) and the spreadsheet he developed was a great tool. then I would create a new "Houston Group Grain Buy #6" and post a link to it here and maybe in all of...
I've competed in many Dixie cups over the years, I believe this year will the 30th. I came in third place back in the 80's but no show last year. It's a great event and will definitely be there this year.
I do ten gallon batches in a keggle (15.5 gallons) and can easily get boil-over at 13 gallon pre-boil, so from a hardware standpoint if you want to do 10 gallon batches go for 50% extra capacity.