Seeking help about refunding on recently free DiRT Showdown game

You have 14 days to refund a game, not 3 months.

Steam Refunding is an automatic process at first and in most cases. To ask for a refund:

Go to Steam Help (help.steampowered.com) and log in with your Steam account.
After you have logged in, click on A Purchase.
Find the purchase you would like to refund and click on it. ...
Select the problem you are having with the product.
Next, click I'd like to request a refund.

You can also do this in the Steam Client if you go to Help>Steam Support!

1 - Not usually, see 2.
2 - Depends on time after purchasing (usually 14 days afterwards) and has been played for less than 2 hours - But there have been exceptions, just try..
3 - Not necessary/Doesn't matter.
4 - If you fall inside refund rules - instantly.
5 - Not very likely.
6 - Only if your key is invalid.
7 - Yes.

TL;DR Just try refunding it and see if they accept it.

Steam has tightened the reins on the refund process.

The reason for this should be obvious -- if they didn't enforce the two week period or two hours play time, people would buy whatever they wanted, then when it goes on sale for a lower price refund it and pocket the difference (pretty much what you're wanting to do).

So you paid 1,49€ for DiRT Showdown and now few months later you want to refund, because it was free recently. Are you insane, greedy and/or poor, and im sure you got this 1,49€ from selling cards. Lets say i got XCOM 2 for 49,99€(full price) before this month HB Monthly bundle for 12$ that also include few more games(if i remeber whole bundle has 100$ worth of games including XCOM 2) do you think i should get a refund, beacuse i dont.

I bought dirt showdown on steam 90% off on DEC 28th and missed the refund window by a few days when it became free on humble. I would be amazed if you get even a reply, never mind a refund.