That seems possibly average. I purchased my 330i with 100% options including Xenons (which i see this one doesnt have), DSC, Heated Power Seats, and a host of other options (though no CD) for about 27000 with 31K miles. Also mine is a 2001, dont know what year this is but the mileage is the only thing that could be a cause of concern for some potential buyers. Even though its fairly understood that higher mileage is not necessarily bad these days in terms of mechanical wear, from a resale standpoint it still hurts you no matter what.
EDIT: Heres a quick rundown by Edmunds with some of the most popular options for a 2001 model.
Trade-In - Private Party - Dealer Retail
National Base Price $22,722 $24,633 $26,397
Optional Equipment $1,567 $1,695 $2,017
Heated Front Seats $252 $273 $325
Rain Sensing Windshield Wipers $76 $82 $97
Leather Seats $541 $586 $697
Power Moonroof $530 $573 $682
Automatic Dimming Rearview Mirror $67 $72 $86
AM/FM/CD Audio System $101 $109 $130
Gray $-54 $-58 $-62
for Zip Code xxxxx $-142 $-154 $-165
67,000 miles $-1,798 $-1,798 $-1,798
I think youre DEFINITELY OK at 25 on the button, maybe a lil more for buffer, like 25650. In your market they may also be in more demand so you might get lucky and hit your target.
Be careful with some of the used M3s out there. I was reading (on the Caddy Forum no less) that some of them had some severe engine problems that BMW was simply ingnoring the issues on which is scary. If you want to know more ill get you the information.