Here is a helpful hint: don't build enough rooms to qualify for the next star until you have saved up quite a bit of money. Once you collect the next star, everyone expects you to have all the latest amenities and your popularity goes down if you don't. Then your rooms don't get full and you lose business and money while trying to buy the latest luxuries. If you wait to build the required number of rooms once you are sitting on a nice pile of dough, then when you level up you can get what everyone wants right away.
it doesn't say level complete if you have white cells with more than 100 in them. =~( you have to wait for them to get down to 100 or move the extra out.
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 "Nano War 2"){kind=icon}
 "Skinny"){kind=icon}
 "Loved"){kind=icon}
 "Kill Osama Bin Laden"){kind=icon}
 "Recordshop Tycoon"){kind=icon}
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 "Fish"){kind=icon}
 "A Bonte Escape"){kind=icon}
 "SteamBirds"){kind=icon}
 "Hippolyta"){kind=icon}
 "My Pet Protector 2"){kind=icon}
 "Robot Wants Kitty"){kind=icon}