What are these speakers that came with my home worth?

I am NOT an audiophile.  nowhere close to knowing anything about audio.
but my home came with Meridian DSP6000 & 5000C digital speaker system with Velodyne woofers (18").  

how much should i sell them for?  a home theater company that i'm working with said that these are easily $15k+ but i'm not sure.   

very much appreciate your help!
hifishark is also a good resource to see what like items are selling for (or have sold for - click the sold/expired tab).
Thank you so much everyone for taking the time to respond. 
Just to answer the earlier question, the Velodyne subs are DD. 
I will look around and list. With hope someone local in the Bay area really wants them 
although dated those dd subs still keep up with some of the best subs made.  They lose a little demand for being 18" which is pretty large for most peoples homes.  The meridian are amazing speakers but also a bit dated and not often looked for.  That being said original price was closer to $25,000.  Current market is about $800-$1200 for each sub.  $1500 for the DSP5000 pair and $2500 for the DSP6000 pair if priced for pretty quick sale.  Id say $6000 mentioned above is a good ballpark

   The owners of a $9000. REL Studio III and a JL Audio F113 wanted to compare their subs to my subwoofer at the time a Velodyne Digital Drive 18. The combined consensus of the comparison was the F113 coming a close second to the DD-18 but only when fed the manually equalized Velodyne signal. 
   The REL owner sold the Studio III a few days after the comparison. REL has gone through many changes none of which seem to have been directed to their fundamental sub design.

   Since then Velodyne introduced their Plus series followed a few years later by the JL Audio DARO version still lacking extensive manual EQ and a $1900. optional CR-1crossover.
   Reading the SVS Ultimate setup procedure they include three memory EQ presets and a Q adjustment a notable DSP direction. 
   Aged and recently out of production the onboard conveniently remote controlled Velodyne Plus AFAIK is only approached by one or two third party equalization programs. The digitally servo controlled Velodyne DD series still provides one of the lowest levels of distortion and is far from outdated. Third party service is available.  

I can help with regards to the Meridian equipment.  Pricing depends on condition as well as version of electronics inside the speaker.  Please look on the backs of the speakers- both of those models were originally released as 18-bit ones, but could be upgraded to the 24 bit versions.  If you see a sticker on the back that says 96/24 then they are a later version (either from the factory or upgraded) and are worth more.  The sticker denotes that the electronics within the speaker have been upgraded to support 24-bit 96kHz sampling.

You can also look to the displays, older speakers have a 7-segment display, while newer versions have a dot matrix display.  All dot matrix displays are the 96/24 versions.

Assuming they are in good shape, no major flaws, have grilles and glass with no cracks, the DSP6000s (96/24 version) are in the $2,000-2,700 range. The 18-bit ones (without the sticker) are in the $1,200-1,900 range.

For the DSP5000C, this one unfortunately isn't worth much.  A perfect one 96/24 from the factory goes for the $350-$500 range.  The 18-bit version (again without the sticker) goes for $200-325.

While these are older speakers, they sound incredible when correctly set up!  The original retail price of the 96/24 versions of the DSP6000s was $24,995.00 and the retail on the 5000C was $4,995.00.  These were very expensive when new, but also note this was over 20 years ago and current resell values account for depreciation.

If the owner had the original boxes it will also help the sale.  The DSP6000s are about 140 pounds each, so without the boxes, you are stuck to a local sale or will have to have them crated to ship safely at added expense.  

How are you planning to sell these?