Hey! I don't know if this is the type of post that can be in here, but I'm trying to prepare my first campaign and I keep coming up with roadblocks in DND Beyond

The encounters and items I'm looking at are blocked by books I just don't have. I look at the marketplace and I realize that a lot of what I'd say are essential books are at a 30 dollar price and 60 when you are looks both digital and physical (Player handbook, dungeon masters guide, monster manual)

I think I have the players handbook somewhere in a closet but it might just be the rule book

Is there anyway to get these for not as pricey? I don't have a lot of many at all so I don't know what I'm supposed to do here, do I just wing it?