Building landmarks and completing the board is part of Monopoly Go's gameplay loop. The more you complete, the more new ones continue to pop. Seriously, how big of an empire does this old man want us to build?
It also gets increasingly expensive to finish a board as you progress. We are speaking about throwing trillions to see through when you're late in the game. On the positive side, you get rewards for completing them, and combining them with events like Board Rush will net you a decent amount of dice.
That said, here's how far you can go building boards in Monopoly Go.
Total number of boards in Monopoly Go
Boards in Monopoly Go are infinite, and there is no end to how far you can progress. There is, however, a fixed number of unique board designs, and it is currently believed to be more than 150 unique designs.
That means you can continue building as long as you like, but the designs will start to repeat once you've exhausted the unique ones.
If you're already 200 to 300 boards into Monopoly Go, click on the three lines on the top right of the main menu and head to the map. You can see all your previously completed boards there, and if you scroll through, you'll easily fetch repeated boards with the same name and designs.
Occasionally, you'll see the new 'Bank of Monopoly' board filled with only rewards. It'll arrive after every ten boards you complete but doesn't add to your board tally.
Tips for building boards faster in Monopoly Go
The best strategy for building boards faster in Monopoly Go is to play during events like Builder's Bash, Cash Boost, Mega Heist, Landmark Rush, and Board Rush.
Because you'll need plenty of cash, try to land on a Railroad with a higher dice multiplier. It is also best not to build slowly, one by one. Instead, collect just enough cash and then go for full completion. Remember to back out just before your one final upgrade so you're not missing on spins either.
By building in one go, you don't leave landmarks half-complete or a large amount of cash in your bank, so there is no risk of losing them to a Shutdown or Bank Heist.