If you are asking this question you shouldn't be buying expensive pinball machines. They are investments in fun times for you, your friends and family and not financial investments. Considering inflation and the fact that you could invest your money, you will not be getting rich off of having pinball machines sit in your basement. I think a safe bet is that DI will decrease a bit over time my guess would be you could sell for $1500 less in 2 years from now but that's just a guess. Play the heck out of it and enjoy life now! Or don't and invest in your future.