Estate sales are often great places to find bargains. Today’s custom BMW E39 is an Estate that’s for sale, but will its M5 updates make it an unbelievable bargain?

If you look at the distribution of model year prices for Porsche’s 911 you’ll likely find that it’s a pretty flat curve lying way up out of the average person’s reach, with a notable dip around the 996 edition. In comparison, prices for Chevy’s 911 competitor, the Corvette, follow a fairly standard inverted bell, or well curve. The oldest models command substantial prices. Those in the middle seem to be more prevalent and manage lower demand so their prices are commensurately weak. Newish cars again get decent bank, owing to their limited usage and contemporary capabilities.

Yesterday’s moderately modified is a model that falls right near the middle—down the well so to speak—and hence the 75-percent Crack Pipe loss realized at its $22,800 price also seems to be ‘well’ in alignment.

You know, we’ve had a couple of owner-modified cars here on the week’s downward slope, so why don’t we just finish things out with yet another one? I think this one might just be one non-factory ride you could get behind, and maybe even into.

First of all, I have to point out one disappointment with this and that is that it does lack a plaid gear knob which as we all know from is the new hotness and my current obsession. With that letdown out of the way, allow me to point out that this is by all other aspects an E39 Estate made M5 mad.

No, BMW didn’t offer such a beast from the factory. The thing is, most of the go-faster parts just bolt right on. Not all of them do and one of the most remarkable parts of the depth of this conversion is that the M5 Sedan’s trunk pan has been welded in on this car, eliminating the spare tire well, but providing room underneath for the quad-bomb exhaust. That’s like Daniel Day Lewis level dedication to the role.

The seller notes that the car started life as a 540i automatic and was originally sold by a Bimmer dealer in Missouri. As most things do, it found its way to California where it was bought by an individual with a vision, and that vision was of one fast wagon.

A donor M5 sedan was obtained and all of that car’s unique features—everything from the S52 mill and six-speed Getrag 420G to the interior and exterior elements—were transferred over. The project changed hands mid-completion but was wrapped up by the next owner. It has been under the current proprietor for the past four years and 4,000 miles.

The car looks to be in damn fine shape, and apologies for the dealer watermark on a number of the pictures. That’s just wrong. What isn’t wrong is the S52 sitting under the hood. That makes nearly 400 horsepower and, in my experience, sounds like the flatulence of the gods. Behind that is the aforementioned six-speed and that sends power back to an LSD. Style 65 wheels in dark nickel fill the arches and those are fitted with a mishmash of Bridgestones in the front and Michelins in back.

The interior is all M5 too, right down to the instrument pod. The back seat in the Touring is different from the sedan, but the seller notes that it was re-contoured and covered in leather that matches that on the front cabin sport thrones.

Is it all that great? Is this as mythical as a fruit-flavored unicorn fart on a sunny day? Well, yes and no. To be sure, it is an M5 E39 wagon, and that is like unobtainium made excitingly real. On the other hand, it’s also an old car with a number of issues that old cars typically exhibit, and a couple that are unique to this particular car’s M upgrade.

Props to the presenting dealer for presenting the car in the ad warts and all. In there, they note that the paint shows well, but does have a few chips here and there. The glass is all original but again there is a small chip in the windscreen. All the lights work with the exception of the halos, while the wipers front and rear need to be refreshed. See? Old car stuff.

The interior come across better with good leather, clean carpet, and an intact headliner. The only noted issue here is a noisy passenger door window. The IP display is good and the gauges all work. On the down side, the airbag light is on. That’s attributed to a buckle issue, but WTF, right?

Mechanically things are similarly decent but not perfect. There’s the note of some weeping at the bell-housing which most likely indicates a rear main going south. Other than that, it’s said to run well, shift as it should and stop without any drama for your mama.

Mileage is 134,000 on the car and an unknown amount on the M5 bits. It’s had a recent oil change and cylinder leakdown test and is at present un-registerable in its current home, California. Yes, womp womp, California dreamers.

It was once registered here, however the owner let the registration lapse, and anyway you need a smog test here to transfer title and this car in its present state won’t pass the visual inspection. That’s due to a missing heat sensor, and the seller says that is no longer available from BMW. If you live outside of the Golden State, this might not present much of a problem.

The $24,990 price tag might however, and it’s now time for us to contemplate that asking in relation to the car as it’s presented in its ad. What do you think, is this M5 Touring worth that kind of scratch? Or, is this a mythical beast best left to legend?

You decide!

Orange County, CA , or go if the ad disappears.

H/T to Alan Arshansky for the hookup!

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