How much does [Insert Season] Getaway Event cards usually go for?

Well, on winter sale my cards went for around 0.50€, but the summer sale cards sold for 0.15€

0,30 EUR or some price like that. Except when they are mystery cards. They go for 1+ EUR. But Valve has been deleting these cards to keep the balance of the normal ones. Summer Getaway 2013 cards are the latest, which still can be bought.

You can only really obtain 1 or 2 a day unless your buying everything on sale (usually)

If you're lucky and get a card right away,you can probably sell it for around $1; It quickly drops in the hours following the event release to ~40 cents each card around the end of the first day and keeps dropping more and more as time goes by. Lowest I've seen them go is for 5 cents when people are panicking just before they expire but other people didn't find out yet that they can complete the badge for super cheap.

You get 1 card for each 3 community votes you participate in(1 new vote every 8 hours),1 card every time you spend x amount directly via steam(I think it was $10?),and iirc also 1 card for each badge you craft(don't quote me on this,it might be a chance to get one). I imagine if you can get a card set for really cheap you may be able to cover its cost or even make a few cents out of it,depends on how early you craft it and how much the set cost you,but don't expect much. Note that there may be extra rewards for crafting badges(I think you could get tokens last sale,which sold on the right time for $5? It was luck based to get them,though.)

If you vote every time you can and sell the cards immediately,you can get around ~$3 through the whole event.