Well I'm here to tell you that you can build a wine cellar for way less than that. We built our house in 1993 and once we were moved in and settled, I embarked on a cellar build with the help of my father-in-law, a professional contractor for most of his career. My basement is not quite square and I picked the not square corner to put up two walls with a door. This would give me a L-shaped cellar with room for metal grid racks and shelves in the skinny part of the L. Each shelf was designed to hold 4 cases of Bordeaux in the wooden boxes they ship in. Though there is room for about 2,000 bottles I never approached that number. At it's peak, my cellar had about 700 bottles in it, the vast majority costing me under $30 per bottle. For someone just beginning on their wine journey, there are plenty of 15-20 dollar bottles you can purchase to experiment aging with.
Above is a picture of the interior corner that uses the poured concrete walls of my basement and the skinny part of the L with the case boxes. Now my cellar isn't completely airtight but it's been absolutely perfect for aging bottles. I still have some Italians, Cali cabs and Bordeaux from the late 80's and they are in perfect shape. Because there is some outside influence, my cooling unit doesn't even run in the winter as my cellar temp drops to around 50 degrees.
As for cost, the total cost of my cellar in today's dollars would be about $2,500 in materials - tops. And that includes about $350 for the materials for two walls including two inch thick foam insulation, $600 for 6 black tie grid racks and $1200 for a through the wall cooling unit that I don't even have anymore - and here's why. This past June my through the wall cooling unit died after 10 years or so of dedicated service. When I went looking for a replacement I found that they were now about $1200 for my sized cellar. The sales rep also told me that the shelf life of these units was about 5-7 years. Well with a kid in college and the higher cost of everything nowadays, there's no way I was going to spend that. So I went looking for alternatives. I found a forum thread where the guys were chatting about cooling with off the shelf air conditioners and it made a lot of sense. So off to Sears I went and I bought a 5,000 BTU window air conditioner for $180. We modified the opening in the wall of the cellar and installed it.
I was miffed at first that despite the control being set at 60 degrees, the unit only brought the temperature down to 65 degrees. Then I remembered a post in the thread I had read that said that you could fool the air conditioner into cooling a couple of degrees cooler by pulling the thermostat, which is connected to a wire, out of the unit and letting it dangle in front. It worked! Now the unit cools to 62 degrees, which is plenty cool enough for my purposes. The energy saver mode lets the unit run only when it needs to. In addition, having a more powerful unit than I would normally need for the size of the space I'm cooling keeps the humidity from dropping too low. It's keeping steady at about 50%. Now if you add up my materials cost you're talking about $1,130 in materials for a 2,000 bottle cellar. If your handy with a hammer and the other tools you'll need, it's about 2 or 3 days work. Even if you have to hire someone for the build, you're talking another couple of thousand dollars which is still way less than the fancy cellars. Cheers everyone.