My question is when does one get out of a trade or sell off a crypto investment?.
It's simple. If you think you have gathered the profit you wanted then it's safe to say that it is time for you to sell your crypto.
Dump a long term cryptocurrency you invested in? What level of loss can you take before you hit the panic button?.
Actually it's up for the person to do long term trades and it's also up to him to pursue a short term trade. I think I can hit the panic button when the trade loss was 30% or something? That's when I cut loss.
OP, you need to read news about the coin you are trading in, since crypto coins are based on events also. It might help you to decide which is which.