I get all my stuff from Amazon (get my sd cards from there), so always free shipping as I'm a Prime member. Everyone at the house splits the cost because you can share the prime account with anyone living at your address. It's about $79 a month, but I buy a ton of stuff every year (especially at Xmas time) so I save a lot, and if you need to rush something, one-day shipping is just $3.99.
If they offer Prime to Alaska, Hawaii (don't know about Puerto Rico), it may be very worthwhile.