Thanks Bujutsu, nitrolures, I_Love_Stamps.
Great advice, thanks!
I noticed a Belgian meter impression in there. Are there other ones as well as Canadians? -> Not sure, I'll take some more photos.
Are there any contents or just wrappers/covers? -> I have about 29 more boxes to go. I would think it would take about 1 hour to look at each box, I'll keep an eye on old checks - good idea.
Do you remember the movie Raiders of the Lost Ark? Here is the warehouse scene at the end of the movie. Kind of reminds me how big the amount of time is needed keep care of a large stamp collection. Gathering of material, cutting of envelopes, sorting of stamps, soaking stamps off paper, drying stamps, making stamp piles, putting stamps in envelopes or albums, listing stamps in
ebay auctions, going to the post office to mail the auctioned off stamps. Licking old stamps to envelopes, protecting stamps from foxing, insuring the collection, keeping a collection safe from moisture, theft... One thing that has made collecting stamps more enjoyable is the internet of course for identifying what you have. Lots to think about!

