Post Cards

Flushed with my success with Ken King (http://www.sourceimaging.ca/), I decided that a set of postcards would be a good idea. My colleague Michael Belfry is a master at this. I can’t reach his level, but I can come close.
I figured on a dozen sets of cards, one for each of 12 topics, to be mailed out at monthly or bi-monthly intervals.
The Canada Post web site tells me minimum and maximum dimensions for a post card within the allowable range for regular letter rates.
I decide to go with the minimum size - 9 cm x 14 cm. I figure I’ll get more cards per sheet that way.
A simple spreadsheet tells me that I can get the most small cards per page (4!) by using a legal size sheet in Landscape mode.
A call to Ken reveals that his sheets go as big as 46 cm x 31 cm or thereabouts.
I recalculate and find that I can for 2x5=10 small cards per sheet.
(In typing this I now realize that I don’t have to go to the smallest allowable; I can expand my size until I reach the limit for 10 cards per sheet. I stretched to 9.13 cm x 15.22 cm).
Ready to roll, I email the specifications - full color, glossy both sides, images etc. I issue a sample document showing my return address in the top-left corner (Canada Post tells you which parts of the card you may/not use), and ken calls me.
In passing we discuss that return address. Do I want it black?
I realize that that side is my mass-mailing side, and it had better be printable; certainly not full gloss!
Saved by communication, drafts, “measure twice cut once” my carpentry teacher taught me.