Hey @Beau Wollens. Welcome to BiggerPockets. You are correct that there is a lot of variability in prices. Even from contractors on a project you can get quotes that vary by 50% or more. The big thing that determines the price is what actually has to be done and the finishes that you select.
I know you said it is a gut remodel but are the floors still good? Is the layout still good or are you moving lots of walls? Is the roof good? Is the foundation good? If the foundation is good, the roof is good, the floors are good, the layout is good, you are probably saving at least $100k right there in labor/materials.
The other thing that frequents adds a lot of cost is when the unknown occurs. We had an underground oil tank that we thought was a 270 gallon. It ended up being about 1000 gallons. Removing it cost us an additional $5k over our estimate. When you have things that you do not know how bad they are until you open up pandora's box, it is hard to perfectly predict the cost.
I'd be happy to have a more in-depth conversation if interested. DM me if interested. I'd love to share whatever advice I can.