I love it, and do all the leg work. I'm very fussy but DH really doesn't care, so he leaves it to me. He'd buy the first car he saw, regardless of make/model, colour, spec, etc - he really doesn't care about cars! I spend hours doing research, decide the exact make, model, spec, colour, age, mileage, etc that I want and then put the exact details in the filters on the website to gauge prices, availability, locations, etc. I go to relatively local garages to do "sit ins" and maybe test drives if I like it. Then often change my mind when something isn't right and "tweak" my specs and go through the process again. Sometimes, I can take several months or even a year or so to find the next car. I'm never in a hurry!
For our last 2 cars (a large one and a small one), I became an expert on the handful of makes/models I had on my short list - I knew the differences between the models, etc., knew the dimensions of the cars on my short list, and knew market prices, which gave me confidence and facts to haggle when I finally got to the final stage after finding the exact car I wanted.
Very happy with the current two cars - both exactly what I wanted, right spec, right mileage, right colour, etc and more importantly, haggled some decent discounts from each garage by showing them printouts of identical cars for sale for lower prices elsewhere! A good result both times.
Already started doing research for what I want next time around. But then again, I do the same with everything else too, i.e. washing machines, cookers, fridges, TVs, laptops - I love to delve into the detail, do lots of comparisons as to features between makes and models, etc. I'm a very "detailed" kind of person and never buy anything in haste without knowing ALL the facts.