I agree with Gonzobob about trying to purchase one used. The reason being most of the stock equipment you will toss away almost immediately. I have a Nanocube 12G that I bought on Craigslist back in Nov 2008 and took out the sponge and bioballs the previous owner had in there. The canopy stock light was not working and the previous owner said she went through two ballast replacement on it before giving up and getting a single satellite fixture. I had trouble keeping my clownfish in the tank with the open top setup so I replaced the light with LED retrofit from Nanocustoms. Love it! I get the intensity of metal halide without the heat issue. I also converted the middle chamber into a fuge. Most nano skimmer are not worth the trouble so I run mine skimmerless. No problem as long as you practice good husbandry.
I'm keeping only a pair of clownfish and a variety of LPS/SPS.
All in all, I'm pretty happy with the tank. If I had the option, I would probably have gone for a 24 gallon version. I wanted to get back into the hobby and keep my wife happy too so the small one works out.