That's a gorgeous car...although i wouldn't pay even what the bidding is at right now (~5700), much less what it will go for 5 days from now when the auction ends. Not to take anything at all away from it, because that car is pretty much perfect...but I've seen similar cars go for around $4K. The big issue with these cars is the difficulty of finding a car that is the "total package" -- that is, low miles, no rust, and unmolested (or, if it has custom modification work, work that's very well done and that fits your taste, i.e. a clean and well-done B-series or ZC swap).
Because of the good gas mileage, age (the newest CRX is now 15 years old) and longevity of the CRX (as in, they run FOREVER), the great majority of them have pretty high mileage these days. Because of the performance and flexibility of the cars, tons of them have had crudely done engine swaps, body kits, painted interiors, and other crap done to them. And, because of the thin sheet metal, problem areas, and age of the cars, rust is pretty common, especially in certain areas that are relatively difficult to fix (quarter panels).
All of these factors, combined with the fact that the cars are getting increasingly rare as they die off, rust, and get low-quality modifications done to them by well-meaning enthusiasts, means that the price on a low mileage, clean, rust free, and unmodified CRX will continue to climb, possibly into the "holy sh1t" range. I know cars are generally poor investments, but picking up a clean CRX if you see it for a good price could actually pay off upon resale a few years down the road.
The exact same thing happened to domestic muscle cars over the last several years. Lots of TV shows like Overhaulin' helped to drum up interest in owning and customizing classic cars, and Baby Boomers with money to burn decided to pick up cars that they owned or dreamed about in their youth. As a result, it didn't take long for the cost of these cars to go from a pretty reasonable level to aforementioned "holy sh1t" levels. It used to be only rare/high performance models or cars in incredible conditions that went for sky-high prices...now, people are paying the same premium prices for rough cars that aren't even rare or original (like straight-6 Mustangs with V8 swaps or 318cid Mopars (with or without 383/440/Hemi swaps). These cars, even when in pretty good shape, used to be the dime-a-dozen cars that Joe Sixpack could buy and work on, because he didn't care about "matching numbers" or what engine was originally in the car, he cared about getting a car at a good price and wrenching on it to make it into something of his own...but now, those same dime-a-dozen cars are going for astronomical prices, and are often out of the price range of an everyday guy looking for a clean starting point for a do-it-yourself musclecar project.
Look for the same thing to end up happening to the CRX at some point. At first just the ultra-clean examples like this silver Si will go for high prices, but it probably won't be long before we are scratching our heads trying to figure out why a DX with a rough D16 swap is out of our price range.
