Tip for everyone who struggles to spend enough money on peacekeeper to level him up (LVL 3 to LVL4) Do the barter trade for intelligence (2x diary, 2x slim diary).  
Not only is it cheaper then buying intelligence on the flea market, but it also counts as 2300$(!!) spend!

Don't know if this was intended or not since 2,3k seems way to much for me.