Obviously you can compare to the near by market to estimate, but can you get to a more accurate number?

I recommend contacting a few that have absolutely no connection with who you are purchasing the property from to make sure your projections of rent and the area are accurate.

How much your remodel costs depends on a whole bunch of factors, including:Where you live.What room you’re remodeling.How extensive the job is.How many and which professionals you’ll need to hire.The materials and finishes you choose.You can use a resource like the Remodelling Calculator to get started, but the more accurate your estimate is for your remodel, the better the chances of staying within your budget and avoiding unhappy surprises.

Do you know how to accurately calculate and divide up the costs to NNN it?

Then you can get a more accurate sense of who you are hiring as well as how their work ethic is so you’ll know ahead of time what you’re getting yourself into. 

I think I found a Deal but one of the things that makes me not moving forward with it is not being sure about the numbers. The asking price is 370,000 and the comps go anywhere between 270,000 up to 490,000 in a .5 mi...

At the auction, I’d expect this to likely go for $350-$425k, IF your value and rehab estimate are accurate.

It's free and I usually am able to get a 50% success rate finding accurate phone numbers

The assessor information on the property is not accurate; sqft off and bedrooms/bathroom off. 

Due to my lack of experience, I have a hard time accurately plugging in numbers such as closing costs, fixed/variable expenses and any necessary repair costs, although I have connected with a couple contractors to help with that.