D&D 5E Best Roll20 products for tier 1 and tier 2 monsters

[FrogReaver]

I’m starting to DM more again for our group and thinking about buying the roll20 versions of a few different books so I can get easy access to their monsters.

What are the top 3 monster products (5e) for roll 20 you all would recommend?

 

[Retreater]

Monster Manual, Tome of Beasts (Kobold Press), then potentially Tome of Beasts 2 or Creature Codex.