OKSGlad ... How nice ... and your generosity I am sure is rewarded each year with buyers "fighting" it out to get your quilts! With $300 added to the funds, you have done yourself proud!
W4Me ... I know what you mean ... I didn't find anyone who came up with that magic number. Wonder if you contacted some of those who have posted to the QB, if they have records of such? The other way is to pick a constant but go scrappy .... eg. all WOW, or all creams etc? Or be like me and just pick a fabric you like that would be well-used in other projects and just go for the whole the bolt!
Just filled the cauldron .... potato soup brewing for supper and the freezer!