Comparing scenarios/forecasts in Excel
 

Hello,

I would like to be able to compare hypothetical scenarios to see which
scenario is more economical. I have a basic understanding of Excel, but I
don't have any formal training in Excel or accounting and I could use some
help.

One scenario I'd like to run is living alone versus living with a roommate.
I need to know how much money I will save in total debt cost by applying the
money I save by not living alone to the debt.

Likewise, I would like to compare the total mortgage costs of buying a one
bedroom condo and living alone versus buying a 2+ bedroom and living with a
roommate(s).

How difficult is it to customize Excel to do this kind of number crunching?
Are there 3rd party freeware applications available?

Any suggestions or thoughts are greatly appreciated.

Thanks,
Nemo