You have to buy farm vehicles for each part of Sakura, there are 3 differant areas, hence 3 vehicles per area. Check the market for sakura, water and zen vehicles.
If you didn't pay enuf attention...like me...to what you needed to do to unlock the chests, then you have to use FC to unlock tiles to open them. Which sucks, since they charge waaaay too much for most FC items, including opening tiles?? Come on Zynga...lighten up! I can't get the final prize because I can't open one chest…