I can't recall the gold amount, but I'm pretty sure it was the Sky Golem mount!
I mainly use the AH to sell.The most pricey item I ever bought item is the Vial of the Sands since I got bored of farming mats for it :D
Most of the time I don't buy anything, just sell every god damn thing I can.But then, the black market came... And I REALLY hope for that Sweet Zulian kittsy to drop one day!
Most expensive thing I bought on AH is probably a WoW Token. Those things are pretty expensive in EU. I'm kinda jealous of US players in that regard.
The most expensive thing, other than the WoW token, would have to be the jeweled panther mount: the black one. Got it for 81k, which was a steal I couldn't pass up.
Hands down has to be wow tokens! Them little things skyrocketed in price! I did however use them to buy Twilight and the Luminous Starseeker.
My most expensive purchase on the AH was definitely a game time token, I never found the idea of getting anything from there through spending gold that appealing. True, grinding/farming can be a pain, but it still got its charm.
I rarely buy anything in AH. :D I usually buy only food or potion. So my most expensive purchases are wowtokens. I never felt that I need to buy anything in AH.
I'm an avid pet collector. I have lots and lots of extra TCG cards that I throw up on the AH for gold. We had amassed what was then a tidy sum of 500k then (hubby and I play together) and I couldn't resist. UDE had just pulled the plug on TCG cards, and I wanted that damned thing! So, at 3 am one night, I got into a bidding war. Buyout wat 300k, and I guess the other person was as limited in funds as I was (300k would have put a serious dent in the ability to run both mine and my husband's account), and I picked it up for 150k. It was still a significant sum at the time, but I had my pet. That reminds me: time to check the AH for TCG pets and see if it's ripe for the pickins!
I was in my friends house and purchased all "Mysterious Fortune Cards" , spent about 1kk just to test the odds and my lucky. The result was unexpected, got about 1,5kk so 0,5kk profit. Extremely lucky.
I'm not such a big AH user. my most expensive AH purchase was 2 stacks of Augment Runes. I needed them for guild raid progression and they were pretty expensive at start.
I believe it was elementium back in the day for around 50k!
Definitely the most expensive thing I've ever bought was WoW tokens for gametime @170k each :P Apart from that I would have to say the sandstone drake mount was probably my most expensive single item purchase, though if you added up all the gold I've spent on raid supplies that would definitely be the winner on where mine gets spent. :D
My most expensive purchase was my Nightsaber Cub and Spectral Tiger Cub. I could do anything to get some kitties to complete my Crazy For Cats achievement haha
tbh i dont think i have bought anything over 20k from AH xD i will always farm stuff myself :P even rare stuff hehedont like buying from AH :P
Has to be the WOW Token.. the way it has risen in cost..!
The most expensive thing I have bought was the Hyacinth Macaw. I had been farming that thing for years and never saw it drop. Found it on the AH for around 16k and snatched that bad boy right up :)~ I just remembered you can look at your statistics in game to see what the most expensive bid on a auction is (not sure if that means you had to win it or not) and mine is actually 29,999.99.99 I have NO clue what that even was for LOL
My most expensive Ah purchase is the Token,270k G! That is huge gold for me as i wasnt playing as much before and didnt really get into gold farming. But outside that the most gold Ive spent as a noob was 60k on the 522 sword from BS in Mop,then to later realise it was overpriced by alot!
I don't now if the black market auction house counts, but I once bought a cat, one of the 20 silver ones, for 200 gold. Once I found out that I could buy it on a vendor I could only laugh at how angry I was.
My most expensive purchases have to be WoWtokens, like several other people here. My next most expensive purchase would probably be two of the guardian cubs for 30k while they were still bind on equip. I kept one for my collection and then sold the second after they were removed from the blizzard store.