Warren Buffett has postulate "Better buy good stock at bad price than bad stock at good price". These words are very smart and true and when you are starting position in stock or crypto, you should follow that. I wrote an article how to invest in Cryptos and for those who didn't read it, here it is:
https://steemit.com/cryptocurrency/@cicbar/crypto-investing-guide
That article was how to start position and today I will try to explain my view, when is right timing to close some position.
First of all, it is ALMOST IMPOSSIBLE TO BUY AT LOWEST PRICE AND SELL AT HIGHEST PRICE.
Yes you gonna hear stories from people how they have bought or sold something with perfect timing but in reality only really small percentage of these stories are true. My friend 
One month ago I have bought OKB, OKEx profit sharing token and I have wrote article about it:
https://steemit.com/cryptocurrency/@cicbar/okb-okex-profit-sharing-token-with-great-roi-at-current-price
That was great buy for me, because I have bought OKB at 1.7$ and price of OKB at moment is 6.33$.
I could lie now how I have profit at almost 400% but in reality my profit is still great but smaller. I have sold OKB at 5$. I am very satisfied with my profit and I don't regret even if OKB goes to 100$.
This is very important rule so NEVER REGRET IF YOU SELL TO EARLY.
You can achieve this only if you set your goals and if you sell when you achieve your goals. We all have different goals and desires so there are no clear rules what your goals should be. I can say only that you should try to be realistic when you set your goals.
When I invest at stock market,I have two types of investments. I have stocks that I buy and never sell and stocks for trade. Never sell stocks are dividend stocks for my retirement portfolio and they must have business model that is immune to crysis. Other type of investments are trade stock. I buy them when price drops hard because of something but only if reason for price drop is not something that will damage long term business of company. My goal on this trade is to achieve 20% profit. Many times I have sold to early but I don't care if my goal is fulfilled.
At Crypto, for me is still only one never sell coin and that is BTC. Dough it doesn't have passive income, I strongly believe that long term price will be much higher so passive income will be reflected in price.
I believe in platforms so I plan to keep some of them for long term like NEO and EOS.
Beside that, I trade some Cryptos and when I do that, my goal is to double my investment so to reach 100% profit.
At OKB I had 300% profit so why I didn't sold at 3.5$?
I have rule, NEVER SELL WHEN YOUR INVESTMENT IS RISING UNTIL IT DROPS FOR TWO CONSECUTIVE DAYS.
If it drops after two days significantly under my 100% profit rule then I don't sell. If it is around it, then I sell. With this rule you will avoid many times early selling. That happened with my OKB investment. I made 300% profit.
These are sweet problem when we are discussing when to sell at profit but when is moment WHEN YOU SHOULD SELL AT LOSS?
MOST IMPORTANT RULE for me is NEVER BUY CRYPTOS WITH BORROWED MONEY.Then you don't have to sell if your investment is dropping hard.
I NEVER SELL AT LOSS IF REASONS WHY I HAVE BOUGHT SOME CRYPTOS HAVEN'T CHANGED
When we do our research we have our reasons why we have bought something. If that reasons are still there then you shouldn't sell. I sell at loss only if there is significant change and I see no point of keeping my position. If you do good research this shouldn't happen to often. I did this only few times in my life.
I would like to hear and discuss what are your goals and what rules you have. Sharing your experience can help us all becoming better investors.
Regards,
