According to http://en.wikipedia.org/wiki/Apollo_Lunar_Module the LMs weigh in at about 15,000 kg... What a waste of material. We can't do that, we won't do that.
The entire contract also cost something like $11 billion! (in 1969 dollars) (Need a better reference than http://en.wikipedia.org/wiki/Apollo_mission#Manned_missions.)
We can build an outpost for that.
So, what we are doing instead, is a very lightweight, very low cost operation, built assembly line style. We are not going to build 1 of them, then redesign and build another, we are going to build like 25 of them.
We want them to be modular enough to allow for a small envelope of changing conditions. (But as it has been pointed out, "Modular only goes do far." - Aftercolumbia)
Richard Speck of Microspace will be doing most of this work, as he has a mostly operational lander already... (<50# dry!)
By the time we get done with it, it'll probably be in the 75# range, and man rated...