Yes I'm amassing quite a pile right now thanks to you especially and everyone here. I'm under your advisement to just play many, many games before worrying about what I need to keep in the long run. And I've got your secret shopping tip to pursue so the pile still may grow.
I'm eager to try my hand at printing and playing via stickers on existing tiles and was hoping to determine some donor tiles from my collection. The Cundco tiles are priced right, but with shipping from Germany I suspect a similar amount of blank tiles compared to big box 4 would cost nearly as much.

My current Mega(lomania) capabilities:
1. Two base games, but not sure if the base game has watermarks to distinguish it from my early edition without water marks.
2. Two Inns & Cathedrals and the one without water marks would only be for mega games because a pain to seperate, but this allows all C1 tiles.
3. Two Traders & Builders - much the same, but really only four of the tiles in the earlier version require a tile manifest (or brain that works like one.)
4. Two Princess & Dragon - here you don't need watermarks and this very easy to seperate since one set will have them.
5. Two of The Tower - ibid
And one of the following.
6. Abbey & Mayor - watermarked (all expansions starting with this one have watermarks?)
7. Count, King, & Robber - watermarked. I've also got the later Count start tile with the extra city on the upper right. (Not the best expansion, but the start tile may be of use for some mega games.)
8. Bridges, Castles, & Bazaars - watermarked. I already have a half set of bridges and castles, so not sure if this will remain, but if it does I'm thinking most of the Bazaar tiles are heading to the print and play glue factory.

9. The six mini expansions and Crop Circles II
10. Other odds and ends including wind roses starting tile, the labyrinth, and some pig farm tile from GQ promos that is a starting tile? (Two of those I have now.)
This must be a lot of tiles...and I now have over 500 tiles.

I'm all ready for friends now: