I just IM'd an owner of multiple IFW networks about this and asked him about the dynamic vs. static IP address & whether or not it would be a problem when he checks accounts to verify IP address with address and phone number information prior to approval. His answer:
"There is really no such thing as "static" IP's with 95% of internet service providers. Almost all ISP's are dynamic, and subject to change your IP address at their whim... Turn off your modem for a couple hours, and turn it back on. You will be assigned a new IP address."
As a rule, even with his ISP it shows him at varying locations within his home state. Ironically, he said it's never actually assigned it to the town where he actually lives. Mine does the same thing. So it is safe to say that as long as you are always logging on from home and still show the same ISP & general area, you should be fine