MARANTZ MODEL 10 TUBE AMP/ TUNER AND MARANTZ 7 TUBE PREAMP

The owner told me that amp and preamp was used from time to time and they stopped using it when they removed their ceiling speakers recently.

Sounds to me like a bit of luck that the stuff is still running in that case. It really is a good idea to get this stuff serviced. You'll be hating yourself if a power transformer fails otherwise!
Its not that hard for any good technician. I've rebuilt several model 7s and 10Bs.

Any older tube gear that you expect to press into service will need the filter capacitors in the power supplies replaced at the bare minimum.

Thank you all for your input. Im still negotiating the price so if somebody would give me any idea on how much should I pay or how much are they worth? 

The only reported sales of the Model 10 that I am aware of occurred 15 or 20 years ago. In those cases prices were similar to those of the 10B, roughly around $2K at that time. The 7 is much more common, of course, and relatively recent selling prices shouldn’t be hard to find. (In searching, keep in mind that the 7 and 7C are the same thing, and can be found with or without an original wood cabinet).

I would add that the value of all of the Marantz tube products is dramatically affected by cosmetic condition. For example, if the top of the chassis of the 10 has signs of rust or significant discoloration, or if the 7 has scratches on its faceplate or elsewhere, value would be lowered significantly. Also, burn-marks or other imperfections on the face of the 10’s oscilloscope will reduce value.

If you cannot view these pieces in person prior to purchase, you should obtain photos that are as detailed as possible before committing to a price.

Also, of course, missing or non-original parts can adversely affect value, in some cases even if the non-original parts restore or improve performance. That can present a dilemma when it comes to classic pieces such as these.

Regards,
-- Al

Also, of course, missing or non-original parts can adversely affect value, in some cases even if the non-original parts restore or improve performance. That can present a dilemma when it comes to classic pieces such as these.

Yes- back when the Japanese were scouring the country looking for equipment like this (1980s and 1990s), it was really important to them that the equipment was in original stock condition, despite that meaning that it was essentially unusable! 
So a restoration should be done that makes it really hard to tell it happened.

Did the sale go through? I own a Model 10 and keep a database of surviving units. I've never seen a rack mounted version. I would love to add it to my list of survivors!