What do we know so far?

Currently planned buildings provide the following bonuses:
Energy – +2 max energy. Max level gives 10 energy.
Cheaper travel – 5% cheaper travel. Max 25%.
Attack – +5 attack per level. Max 25 attack.
Scrap after dismantling – +1%. Max 5%.
Box drop rate – +0.4%. Max 2%.
Upgrade costs:
Level 1 – 50 steel
Level 2 – 125
Level 3 – 300
Level 4 – 650
Level 5 – 1400
Total cost to max out a single building is 2,525 steel.
You can have a maximum of 4 buildings, meaning you will have to choose which building to give up. In total, this will cost a modest 10,100 steel. If you have 16,968 BTC, you can buy steel right now.
For the moment you can build 1 extra building for the levels reached:
LVL 5 - 1 st. building
LVL 15 - 2 nd. building
LVL 30 - 3 rd. building
LVL 45 - 4 th. building
You don't want the building?
You can destroy it and get back 90 % of the steel spent.
You can also downgrade by one level and get 80 % steel back for the last level.
Don't downgrade it's better to demolish and build a new one. That way you'll save quite a bit of steel!!!!!!!!!!!!!!!
These are numbers from the beta version. Keep in mind that all of this information is preliminary.
