Lvl 4 xBows surely means level 12 storages and mines/collectors. Maybe up to lvl9 for DE collectors as well.
The lvl3 xBows currently cost 8 millions gold which is the max you can have atm. My only concern is not about the cost of the structure itself or the cost of the town hall (which is probable going to be around 6millions to build in order to incentives people to go for it) but mostly about building times.
PLEASE SUPERÇELL CAP THE BUILDING TIME TO 12 days max. It doesn't matter if it costs more. Building need to be right! They should NOT take longer than 12 days to upgade something in the game. It becomes really silly otherwise.




