My idea, Jansimon, is that each volume of the British Commonwealth e-catalogs is simply the BC countries as listed in the corresponding volume of the full catalog, and that Vol 4 of the full catalog has far fewer pages of BC listings.
I suppose you are right. Still it is weird - if you decide to sell selections of the normal catalogue, why not make one or two new selections that have everything you need. This is even more so with for instance the Scandinavia parts: 4 separate items where it could easily be one.
The concept is still a bit unclear. As far as I understand, you do not get a file to store on your hard drive, but you are granted access to specific parts of the database, right? But what I do not understand is, do you get unlimited access or do you buy a yearly subscription? And what about updates: if Scott adds new items or changes numbers (which they of course do all the time), do you get to see them or do you need to buy a "Scott 2018" update?
I purchased Mexico 2017, it have a very good option for USD$8.00. Is only for reading, cannot be downloaded 
