Selling 1990 XJS-- What should I ask for it ?
Excellent interior and exterior
Antenna in up position, passenger rear window up position, manual top only, top motor does work.
No cruise control.
All else works, heated seats work.
drives like new.

 

Apologies, because this may not be what you'd like to hear, but most of the things you list aren't that difficult or expensive to fix, and though they may seem minor, that many niggling things wrong may really have a negative impact on the purchase price. You are already fighting the perception of legacy brand unreliability and the complexity of the V12. As a buyer, if they see those things wrong, they may feel like the captain of the Titanic admiring how pretty the tip of the iceberg looks.

For instance, I had a rear window not working, tried switching relays, cleaning contacts, etc. to no result. Found a thread either here or on another forum, that with little use the motors sometimes get stuck. Taping on the motor with a screwdriver while applying current worked like magic and it's been working fine since. The most common problem on the Cruise Control is a failed rubber bellows and is a cheap part on rockauto.com.

It might be worth searching the archives here for your problems and seeing if a weekend might reduce the list and raise your possible price.

Cheers

 

Good advice by Mac Allan. You said "excellent exterior and interior". That is THE main factor to an enthusiast; and will be the biggest attraction for a novice.
You haven't stated the mileage, condition/life in the tires, if any engine maintenance has been done such as if the fuel injector hoses look fresh or show age cracks, whether the steering rack feels loose, if it has original suspension bushes. etc. Being a member of this Forum and now an educated enthusiast, those are all things I'd want to know. The Top not working will scare off lots of potential "Novice" buyers IMO. Give us a better description if you really want the Forum's opinion. What color is the interior?

 

Based on your description, savvy Jaguar enthusiasts will lowball you and people unfamiliar will run from the list of non-working issues. It’s quantity, not quality in this case.

As you have it. Maybe a $3,500 car?

Youd easily double it if you just worked that list off.

 

78,314 miles, BLACK INTERIOR
New upper wishbone bushings,
New Dist cap, coils,plugs and plug wires
New thermostats
Tires less than 1 year
New injector hoses
New all 12 coolant hoses
No slack or play in steering, let go of steering and straight down the highway
New trunk spoiler, never installed
Original smog light covers
New fan and fan clutch
Convertible top 5 years old, car always garage kept
New A/C compressor 4 years ago

As Mac Allan and Vee suggested, I will fix window, antena and top.

 

Fix those problems and I'd say you have a $8,000 - 10,000 car. A dealer would ask $12,000. Others will chime in, but it's worth what the "Market" will bare.

 

I was also thinking maybe 8 to 10, will be up for sale in a couple months.