I got the task to place 100 blocks in this quest, I relised that if you place a block then remove the block the count doesn't subtract. So therefore you can buy '1' block for about 1 gold or whatever, and keep using it over and over to complete a quest that would cost like 100. Nothing to big or major but could be used to save cash.
Update: You can just keep placing the blocks in the same place and it goes up !!
note: Also sometimes you get stuck when spawning to [root] casue of the other characters standing in the same postion. And seems you have to press " UP " for it to lets you move otherwise your stuck!