My Lands: Black Gem Hunting

Can warehouses be upgraded mines is full and i dont know if i can upgrade it, i checked the encyclopedia and nothing on it, so what do new players do if their warehouse is full and i dont seem to be able to sell anything yet. Will i still collect gold?

Sorry i posted this in the wrong section could admin mabye move this to questions.

warehouses can be upgraded to 8 levels http://mlgame.co.uk/wiki/Wiki.jsp?page=Warehouse

you can also build more if you have the space