Listen to so much good advice that others are giving you. The most important thing in this hobby is "patience" and truly it is rewarded most of the time. I will give one quick example (I have many but this is my most recent). I just bought a beautiful HUO ELVIS. I missed buying Stretch 2 Elvis a few months ago back for $3,450 (great price). However, the one I bought yesterday I found on CL for $2,800 with very, very low plays HUO. My point.....patience is always rewarded and sometimes I don't follow my own rule....LOL. When I do I am rewarded and when I don't I pay up.....LOL !!! I am learning to be more patient and truly seasonality matters when buying or selling. Better to buy in the summer and sell late or early in the year as prices soften normally in the summer and strengthen around X-MAS and early in the year.....you can save 5-10 percent just by buying during the "weak period" as opposed to the stronger period (hey 5-10 percent can be a decent number on a $6K pin....lol).
Also, I find it is sometimes better to travel if you have a region 2-3 hours away that has lower prices (I find Northern Virginia is always more expensive then say Harrisburg area and one is an hour away and the other is 2-3 hours but the best deals I find are normally in Harrisburg or around those areas....maybe I have just got lucky).
As for IM, it is a hot pin with limited supply. Pros and Cons to buying one. Due to the limited supply and popularity it might hold its value (relatively speaking) then say buying a AVLE.....I know that title seems to go down $100 a month every month lately.....
Finally, I believe in paying extra for a nice condition pin (it is worth is if you try to resell it as nice examples of popular pins have a lot more "appeal" to people then "players condition" so if you get lucky enough to find a pin in GREAT SHAPE for not much more then "players condition" on some of the older titles YOU JUMP ON IT and don't ask questions.....LOL !!! Pins prices are based on condition more then anything I have found.
Good luck to you.......take your time as truly IM price in my opinion will "soften" come the summer so you have time to make your decision.....