at least 14lbs or rock and 14lbs of sand. Depends how much money you want to spend, as far as sand you dry aragonite (no need to go live, save you money for live rock) and as far as the rock, if you have the money you can get all live, if not get some base rock (dry rock) and some live rock. It will all (sand and rock) become live at some point. Heater, yeah most likely. All depends how consistent your house temp is. I keep it cool in the house during the winter to save money, so I have a heater in mine. Protein skimmer you could get away without having one (there is actually another post going on now about protein skimmers & nanos) Of course if you have it, it'll only make it better, but not necessary.
Just curious, why a 14G? I know i started with a 29G BioCube, quickly put up a second tank 38G w/ 10G sump, and I'm looking for a 125G on craigslist.