Expect to pay about 1000 to get it DRIVEABLE...... There will be so many things rotted from sitting.....
Ask them how often they drove it..... If it was driven, say, every couple weeks and allowed to get up to operating temp, then id say go for it.....
No more than about 4500.....
If the leather has been redone, chances are its been done in vinyl, not real leather...... Which means you will have some severe fuse-age of the legs to the seat in the summer.......
Believe me, I have a boat, and its not fun.......
Even if it has a new engine in it, that doesnt really mean diddily.......
A Q is meant to be DRIVEN, not to be show car (although it is good at that also!)