Price I cannot comment on as I've not been in the used CRD market for a while and I don't know what limitations color, leather seats and sunroof place on what's on the market. I also don't know about color; stoutdog's 06 is REALLY red especially when in the sun (
viewtopic.php?f=5&t=69117&p=739421#p739421) and I think the color is Inferno Red but could be wrong (I don't have access to his build sheet at the momement) which is a touch darker than the Flame Red.
As to what to look for 1) see Sir Sam's NOOB guide for CRD specific items/mods and maintenance that should have been done including proper fluids and 2) the usual brakes, tires, battery for any used car purchase. In an ideal world one that has had the EHM, or SEGR or GDE tune from early on would be best to keep soot out of the intake and combustion areas. At minimum dig in far enough to check the turbo end shaft for play and demand a full CarFax report.
I assume you are aware that these vehicles can require some personal hands on maintenance attention although some of the known problems can be avoided by upfront preventive work and of course this forum is a wealth of information on what's really wrong and how to really fix it.
PS - in looking at Jeep KJ colors by year it appears that in 05 both Flame and Inferno Red were available. It would take a better eye than mine to determine which color I was looking at absent a paint chip or some such for comparison although I do know that if you have a vehicle's build sheet that the color codes are different. Bottom line is many online ads seem to say just "red" without saying which red.