Fresh is best, when it comes to ANY flour milled from grains/seeds/beans - whether gluten-free or not. And personally, I'd choose FRESH flour at a higher price, over commercial flour ANY day, because of the nutrition; but generally speaking, purchasing and milling whole grains/seeds/beans is less expensive than commercial flour.
Think of it this way, for every pair of hands it takes to process a food item, the more it costs.
You can grown your own corn to make your own cornmeal and corn flour. Same with beans for bean flour (although all kinds of beans are very inexpensive). By growing your own, you are assured they aren't cross contaminated during storage. If your garden is large enough, you can also grow a small amount of sorghum. I harvested enough amaranth off of 12 plants last year to last me for years. The seeds I used were from the amaranth I purchased at the health food store. So by growing your own, you can cut out the middle man and save even MORE money.
Rice (brown or white) is ALWAYS less expensive than rice flour - and you can easily mill it in a coffee/spice mill. I purchase sorghum from a gluten-free sorghum mill outside of town for pennies compared to the price of Bob's Red Mill sorghum flour. I develop GF recipes for this mill.
I purchase organic yellow dent corn 25# - $15. While Bob's Red Mill sells 6.5-pounds of GF Cornmeal for $9.92 (plus shipping). PLUS, with corn, you can make corn flour as well as cornmeal. You just have to compare prices and find your priced-right sources.
Why fresh is best..... Once the bran coat is broken during milling, the oils quickly oxidize (oxygen) and the nutrients quickly degrade. When you purchase ANY type of commercial flour, it has already lost most of the nutrients. In one study, vitamin loss begins as quickly as 3 hours after milling. Flours that have been warehoused and shelved for several months have lost large portions of their B Complex and C Vitamins.
Fresh flour, high in nutrition, is even
more important to anyone with Celiac Disease because of malabsorption of foods and nutrition to begin with. So old flours are contributing little besides calories (energy), NOT nutrients.
As I've explained before, many of the GF grains can be milled in a coffee/spice mill. Which is also a convenient way to mill if you need it while traveling. But I'd suggest 2 mills, when your budget can handle it. The quality of the flour will be much better with a mill designed for flour.
Nutrimill -
http://www.pleasanthillgrain.com/index.aspx#Nutrimill
This mill will all grains and beans, with the exception of the tiny (teff/amaranth) and oily seeds (flax, sesame, poppy seeds). This mill will also mill a fine-grind cornmeal.
Seed Mill
Porkert Poppy Seed Grinder -
Amazon.com: Poppy Seed Grinder PORKERT: Kitchen & Dining Great for tiny and oily seeds.
I mill a large number of grains/seeds/beans and incorporate them as flour, flakes, or coarsely chopped into all my cooking and baking. I make all my baked goods. The savings on those items is tremendous compared to commercially purchased items.
I mill all my cornmeal - fresh, when needed. Most commercial cornmeal has been de-germed, which is where the nutrient-rich portion of the seed is located. Those products that haven't been de-germed should be packaged in a vacuum-sealed container and/or stored in the freezer to prevent the oil from going rancid - but none of them are. And please note, oils don't have to smell rancid to BE rancid. Oxidized oils are free-radicals and damage our cells. One more reason FRESH IS BEST!
I make my own nut meals. I also make nut milk and dehydrated the coarse nut residue from the drained milk, and use it for nut flour. I make
Flourless Hazelnut Cake - but I wait to purchase hazelnuts after the holidays when they are 1/2-price, and stock my freezer with them. You can't tell this cake DOESN'T have flour in it!!!
The one GF flour I have to purchase,
and love using, is coconut flour. If you haven't given it a try, here are some recipes. It takes very little in a recipe, so a little goes a long ways, but most recipe take a lot of eggs.
http://www.tropicaltraditions.com/organic_coconut_flour.htm
http://www.simplycoconut.com/Coco Flour Recipes.pdf