Obviously, for most countries, you will find a better specialized catalogue, but Scott isn't a bad thing to have. However, it is EXPENSIVE new. As of 2018, Scott split all of its volumes into 2 parts (a good thing -- they would each be the size of a large telephone book otherwise) and retails them for $134.99 for each set of 6 sets of 2.
In practice, a new set is about $650 for the 12 books.
So...a bit of advice:
-- I would say you don't need a brand new Scott catalogue set, or to update it every year. The prices don't change that quickly (except for some unusual areas like PRC) and you're fine with a set a couple years old.
-- It is worth getting the new 12-volume format set. The old 6-volume books are large and unwieldy, and fall apart more easily.
-- If you are in the US (foreign shipping may kill much of the savings) get the books used on Amazon. Piece the set together from different sellers if you have to. I was able to get a full 2018 set for $106 shipped! Took about a week to get all of it, from 4 different sellers.
-- Ex-Library books are good! They have some stickers and markings on them, but are perfectly usable, and they laminate the covers -- they will actually last longer than new ones since the covers are less likely to fall apart, or pages to fall out.
-- Be sure the seller has indicated both volumes of the set are included. People have complained about ordering and only getting, say, a 3B with no 3A.
-- Buy some stamps with the $500 you just saved
Note: You won't be able to get a US Specialized for less than $45 or so, and the Classic Specialized 1840-1940 hardcover is expensive -- $90+ even if you get a 10 year old one. So you might want to skip those.
