Pull up your different powder companies for their specific information on each caliber you are considering and then check your local availability of that powder...
If you have to have powder shipped into you, there is a specific HazMat fee, whether it's one pound or twenty...and your local supplier will usually spread that fee out among his order.
I was recently looking for some powder that would work well in my 9mm, .40, and 10mm handgun loads. I checked the Ramshot line and found one that would cover all three and it's readily available at Graf & Sons, which is not that much out of the way for me and they usually have a good supply on hand..
Since you say you don't shoot much, it may be a once in a year purchase for you, as long as whatever you choose is available...
