Maximize profit on spec home and other questions

[John Hartman]

I am just getting involved in real estate investing and think I found some land that could be very profitable to build a spec home on. I am in Virginia and found a development with several lots selling for around 5-15k. I am currently waiting to hear from my real estate agent but I think a new construction home around 1400 - 1600 sq ft should sell somewhere between 300 and 350k, there was a recent comp that was 1600 sq ft that sold for 335k.

I am still working on figuring out costs to build the house but I think/ am hoping for somewhere around 235-260k. 

Now for the questions, what can I do to minimize costs and maximize value? What upgrades are worth doing? My initial thoughts are to spend money upgrading the kitchen and master bath; granite countertops, tile backsplash, maybe a pot filler over range, tile shower, extra windows?, higher end appliances?. And to not spend too much on things that don't matter too much; thinking flooring or at least carpet to a degree don't want to go too cheap on that, exterior things like siding not sure if there is much money to save there, any other areas to save money?

How much value and cost do things like basements and garages add? 

Any tips on finding a builder to build a spec home, most builders I have talked to, albeit few, are custom home builders looking for 230-250 a sq ft which is way too much to turn a profit