Dates and conditional formatting

I have excel 2010 and I'm making a spreadsheet for two holiday homes, each month will have its own sheet, I need to make the balance hightlighted 6 weeks before the guests arrival date, can this been done?

Also is it possible to display a monthly calendar on the spreadsheet to show what dates are booked?

Am I making this too complicated?

I'm bit of an excel noob so simple is good lol