Sort:  

Not a gamble. You can sell straight away at whatever the price of it at that moment. However, due to frequent changes in demand and supply, the price keeps fluctuating. It would be nice to sell when the price is towards the peak.

For this we have to keep an eye on the daily price. Right?

Yes, definitely!

i have used it metaphorically not literally

Metaphorically, yes. You may (or may not) get a very good price.