Like with everything else, things go up depending on the season.
Summer is coming and that means the most active time for RC.
So prices will increase. During the winter, I have seen AMB's at a stagnent $75-80.
I love MLB baseball but I will never buy anything from March to October. I could buy a jersey for $100 during the winter that would cost me $150 during the season.
Same goes for RC, try to buy your expensive stuff during the off-season.
Only problem is that companies release all the new stuff during the summer!