I have a question for American BBM/Calbee (or even KBO collectors). Basically, where's a good jumping in point?

I found 2018 BBM series 1 for under $40 on Rakuten (https://global.rakuten.com/en/store/.../020220180070/). But I'd like to know what I'm getting myself into. I don't care too much about resell in the states (though, I wouldn't mind eventually being able to turn around doubles, but I'm not buying it to prospect huge hit cards).

My questions, I guess, are: If I get two boxes, would I be close to putting together the base set? Is Rakuten safe to order from? Is $37+shipping reasonable for the quality of cards?

I'm a bone stock rookie on Japanese cards (I lie, I bought 2 packs at a card show in 1989 and thought they were the coolest things in my collection). I also nihongono wakarimasen.

(And if you collect KBO, Cuban or Mexican cards, I want to know how to do that, too.)

Thanks for the hand holding, guys.