Yes, very thorough...agonizing even. But I admire the effort!
There are all kinds of 'Nikonians' who have upgraded from the D200 to the D300 for added ISO performance. They are now selling their D200's for half the price they paid (or less, in some cases.) Many of them only have a few thousand 'clicks' on them (actuations is the official term, I believe.) That would translate to somewhere between $600 and $800 for the body.
By using a free software program called Opanda Power Exif, you can tell how many shutter releases the D200 has. Just shoot a photo, view it in Opanda, and it's one of the data entries returned. Don't worry, the guy who owns it doesn't care that he's only taken a couple thousand shots and is basically selling a brand new camera.
It is characteristic of an entire class of photographers who research and enjoy owning the latest high-quality photographic equipment much more than they actually enjoy photography. Well, at least we can say they enjoy buying new equipment even though they don't really use it much.
I focus on the D200 because
it is capable of being used with nearly every lens made by Nikon since the early 1970's. These AI/AIS lenses don't have autofocus features, but meter nicely on the D200, so you can shoot on aperture priority and simply focus manually.
These can be purchased for bargain prices on eBay and other outlets because most of these same people want auto-focus lenses. I have a 20mm/f4 made in 1973 that takes stunning images. $125. In fact, I would argue that Nikkor's "old glass" is as good, or better, than what you can buy today. I am not a fan of Sigma etc. I would certainly consider the Nikon 50mm 1.8 AF lens brand new. It's cheap and it's performance is excellent.
So, if I had a budget of $1200 and wanted to find a bargain in a DSLR, I would marry my best-featured-for-the-money DX camera to its ability to use the greatest numbers of high-quality, low-priced lenses.
Make sense?
Certainly it makes more sense than paying $1600 for a camera, using it like the price of digital images was tied to the price of gas and then selling it 12 months later for half what you paid.
Try Nikonians.org to buy a used D200. They have had some problems with internet sellers of late, so be sure to get, and be ready to furnish, references. Use PayPal.