I had an 88 XJ6, I loved that car. Sol;d it with 140,000 miles on it a few years back. I still see it on the road.
I replaced it with an 02 X type.
Your car has low miles but a high price tag.
I stopped by a 90 XJ for sale at $3300 US. It had 63,000 on it.
Mine was pretty much trouble free and most of the parts are easy to obtain. My ignition module went on my 88 and I found out it was just a Chevy Module inside a Jaguar box.
Frank