ROI on Premium Decorations and Buildings

"ROI" stands for "Return on Investment" so, basically, "how much crap I get per donut I spend". The purpose is to use your precious donuts efficiently.

Buildings
Buildings are broken down into units (dollars and XP per hour). The units are also broken down into how many you get per hour for every donut you spend. Without factoring in play time, the higher the better. However, if you only check the game twice a day, the Try-n-Save is NOT a good investment for you. If you check twice a day, then you check, on average, every 12hrs so you would want to choose the Observatory, Sprawl-mart, or Asia de Cuba. MONEY AND XP MEAN NOTHING IF YOU'RE NOT AROUND TO COLLECT IT!

Decorations
Decorations are pretty simple: you get a certain bonus % for every item. But there is some math to determine which items is the best deal. This table lists the decorations in order from most benefit to least. For example, the Whale will give you 7% increase on everything, but it costs 300 donuts, or in other words, you are paying 42.9 donuts per 1% increase in bonus. The Jet Engine Bike only gives you a 2% increase, but at the low price of 30 donuts, it has 15 donuts per 1% increase. This means that the Jet Engine Bike is almost 3 times better value for your donuts than the whale.