When to sell is not only in Crypto a pretty important question one should answer themselve but it seems also be important in the coin flipping markets.
As I read myself almost daily through some forums to get a better feeling what people offer, what gets sold quick, what does not and how much gets sold.
For some coins I also track eBay offers.
One thing I look for a lot is the how many of those coins are on the market? Does the supply get refilled quickly if one gets sold or is it drying up slowly? Again, how many get sold, how quickly?
Long story short I try to get a feeling for the volume and sometimes a coin can fall out of favor of the collectors for example the Chiwoo Cheonwang series.
I am not sure yet how useful this data will be to be honest but somehow I enjoy doing this and it is really interesting to see how the market is values different coins and how much the dealers are asking for on their homepages.
The collectables market is quite fascinating and despite it looks quite slow on first glance there is quite a bit going on.
But maybe everything looks slow if your other comparison is the crypto market :-)