You can raise a building's level by spending materials and gold.
Goddess's Prayer, Bank, Dojo and Hall of Fortune max out at Lv30.
The Lodge maxes out at Lv5 and the Lab at Lv42.
Raise the Lab to Lv.42 and
unlocks.
With Quick Gather you can collect 6 hours' worth of materials once a day for free.
You can also collect 6 hours' worth for 100 Rainbow Crystals.
Tap a material you are short of and a Go Gather button appears that opens the map
where that material can be gathered.
You can also buy the materials you lack with Rainbow Crystals.
Raising a building's level earns you Six-Flower Orbs according to the level.