Can someone explain to me why I would have 120 left on my budget and can't place items. It tells me "to many of item on map" even when I try placing an item not on the map yet?
You've hit the hard limit of the map. I don't know what map you're using but every map has a hard limit of how many items can be placed on that map. It's to keep the game from bogging down, and giving crappy gameplay. Try and find different ways to make your structures if you can, in order to save items. And use the OLN canvas's if its a sandbox map.