I do not have personal experience with the BG6500.  Two thoughts anyway:

You should be able to get it fixed by a pro for no more than $200, regardless of what's wrong with it.  The real question is whether it's cosmetically near perfect.

If the MMC2 works still and has the low mileage on it the seller says, the cartridge alone should fetch between $200 and $300.

Thanks!  Any recommendations for such a pro?

The string coming out of the unit is the string that puls the pick up arm mecanism toward the disc, if the arm does not move after pressing play the TT turns of, an easy fix, if by Benny ask to change all bands (2 if I remember right) and change electrolitic caps and do a full service, its worth it, as Rich mensioned only the MMC2 is worth a couple or more hundreds USD.

Get photos from the laterals, the white plastic tends to open at the edges if stored in humid locations, and if the owner stored his remote on the TT, the plastic cover will have a downward "sack" at the back end.

Just took a look on your link, the TT has an aluminum front, this is not normal in a white edition, the front normaly is white!!!!

The rest of his items is aluminum. I dont know if the TTs upper deck is white with aluminum front in aluminum edition.

I'd actually assume that, since the cartridge is untested, it doesn't work.  It's a well-know fact that with these old MMC cartridges the rubber stylus suspension dries out due to age, causing distortion or channel outage.   Given this and the repair and the cosmetic flaws (see the platter), this turntable isn't worth much in my opinion.

It is just dust on the platter.  Also, the entire unit is silver, it is just the angle of the pic.  I verified all of this with seller.  

As above you should really assume the stylus will not work, and if it does you have got a bonus! If a channel out then it will not be repairable, but ok if just needs retipping!