To give a rough estimate about how terrible the RAM prices are, and have been the last few years. As people are hoping for crazy amounts of RAM. Historically, you could purchase the same amount of RAM or more that was in a console for about $50,- when going for the common equivalent available for desktop systems during that time period.
Year, Size, Type
2000, 64MB, DIMM - PS2 (32MB) launch year
2006, 512MB, DDR2 - PS3 (512MB) launch year
2013, 8GB, DDR3 - PS4(8GB) launch year
2018, 8GB, DDR4
RAM prices have stagnated a lot over the past few years. Which has never happened before, not on this scale. This is something that will affect the upcoming generation unless prices drop hard and fast.
*Yes, I'm fully aware that these are not the prices that Microsoft, Nintendo and Sony pay for their memory modules nor are these the memory types that they'll (most likely) use in future consoles.