How do you determine new construction costs and is this a good deal?

[Katlynn Teague]

Good Afternoon BP,

My client is looking to sell one of his lots however, I am very unfamiliar with the costs of new construction. 

My bread and butter is single family fix and flips so this deal is a little out of my wheel house. Here is some information on the lot that might help. This lot is 1.16 acres and 0.6 of the lot is buildable with the remainder in a flood-zone. My client is a general contractor and said it would be perfect for a 4,000sqft home. The ARV of the area is $1.1-1.5m and is in the best school district in Georgia, if we sold this one at $220k would this be a good deal? What would costs look like when building a home of this caliber? How long does it take for a new build?

Thank you so much in advance!