How do you valuate a lot/piece of land for wholesaling?

[Ryan Succetti]

I have a potential seller who is in foreclosure on a lot. This lot is within a Luxury Gated Community. There is an HOA and CC&R's with strict rules of what can and cant be built. For example there is a minimum size of 5000sqft for homes. There are currently built homes that have recently sold in the mid $2 million range. Each lot is set up for electricity, sewer, gas, etc.... . All the buyer had to do get have plans made, approved by the HOA, and build a beautiful estate.
There are 3 smaller 4 plus acre lots listed on the MLS. 2 for $240k and 1 for $650k which massively overpriced has been on the market for almost 2 years. In the last 12 months 2 smaller lots 5 acres have been sold. One for $260k and One for $150K which was an interior lot.
The lot that I am hoping to sell is just under 6 acres and is an exterior lot with amazing views and is one of the larger lots in the community.  

Please help and thank you in advance.