Steamtrades prices question

Every person trade by his own prefferences and as they want, there is no given "rules" that everyone must follow.
After thousands of trades done i can say its more like madness than trading

Check Allkeyshop for ballpark prices.

It's really hard to figure out. I've usually used a mix of ITAD lowest and number of times bundled , but I've seen plenty of people use gray market site pricing, Have/Want ratio (on Barter.vg), and MSRP as well. I find that some people also change their method of pricing things based on the game, so they can get the highest value for everything, which is fine I guess, but makes it difficult to make offers.

Set the price based on the value of the game in your mind. Then there will be no regrets and no need to spend time on searching for the trade