Building upgrades

[skywalker_98]

I know this might sound like a dumb question but how do get to upgrade your money buildings past level 10? I see many that are lvl 15..19..etc any insight would be helpful
Thanks

[truthteller]

I know this might sound like a dumb question but how do get to upgrade your money buildings past level 10? I see many that are lvl 15..19..etc any insight would be helpful
Thanks

when you get to level 10, just keep upgrading to 11 and so on
gree changed so that all money buildings and NEW Boost buildings can be upgraded to level 20