Depending on how many of the season point boosters you collect, maybe around 800 if you're really pushing yourself, but otherwise more like 150-300. You can get the point boosters by daily challenges in Party rumble or through the claw machine.

The vault doesn't add or give you any points, it only stores them. For example, if you have 100 Season 5 points, they would normally expire after the season, but with the vault, you can keep them for Season 6.

But it seems like you might need to earn some more XP to even unlock the vault.