Help, I am trying to evaluate a property in the calculator to find out what my cash flow is but when I put in the numbers I get some crazy results back. 

If you want to learn about a specific market the best way is to evaluate properties in that market over and over again and eventually you will get a good sense of good and bad areas as well as what a particular home is worth.

 What are some recommendations in making sure you effectively evaluate how much money it costs to repair a fixer-upper?

They hired some in-house technical talent to evaluate deals.   

@Walter Ciucevich There are lot of sophisticated ways to evaluate multi family properties.

So, I tucked my tail pretty ashamed and have been re-evaluating my numbers ever since.

I am evaluating a residential rental property and the owner, who has a business separate from the rentals, apparently leases a building on the property (not a rental unit), out to himself for an office for his other business, (this building could be rented out as an office so he is not calling it something that its not). 

If it makes sense I'll evaluate using docusign in the future though. 

I'm very fond of Excel, like @John Warren, but only for certain things, like evaluation of acquisitions, calculating cost and benefits of different loan structures, and projecting cashflow. 

So, I would evaluate that option in some detail before deciding to put in a second meter.