I'm trying to get into the blue building but you need so many achievements! I don't really understand how the achievement page is set up either because I keep getting achievements that I don't see on there! So what achievements do you guys find the easiest to get? I only need like 150 more (ONLY) so I'm trying my best to do some achievement hunting!

The easier ones are the ones where you just have to visit some place or do one thing, sometimes repeatedly. But the level of difficulty or effort of most will depend on how you prefer to spend your time on Subeta. For example, people that have been feeding a pet for years will find the food-related ones easy. I’d suggest just clicking on each category and scrolling through to see which ones you think you can achieve. Also, check the Achievememts forum, because there are a lot of super helpful threads over there, with folks working together to get achievements. Good luck!

There are a lot of wardrobe achievements where people will lend you the items for free, in this very subforum! Look for lending threads.

A couple of the pet color achievements (for more common ones like dawn, dusk, etc) are easy to get if you find cheap elixirs of that color. It will still add up but you can find elixirs for as low as 20k sP or closer to like 60-70k sP (last I checked)