How far have you got and where are you stuck? We won't do your assignment for you, but don't mind giving some hints. Also please use code tags when posting code - and as you haven't, this suggests you haven't read the posting guidelines, so please go and read them before posting further.

What variables do you think you might need? For example in 1 there is a mention of room size; does that imply anything for local storage? What about the other six requirements?

Tackle each requirement one at a time. Do you know how to do 1? If not, can you think how you might modify
cout << "Enter balance: "; // prompt user
to have the desired effect?

Then onto step 2. Can you see how to do that? If not, do you think you might be able to modify
cin >> balance; // get data
to do what is needed?