I want to make a joomla page, similar to ebay, and such, but I lack the skills :p

I need my users to be able to post their items for sale and auction. 24 hours auction and stuff. And minimum price...

Is this possible with K2, you think?

Thx, in advance.

And yes, I know, I should hire a developer, but I don't have the funds...

I would recommend the latter, the hiring of a dev.
K2 can be used for the product's display but the whole bidding/ reserve should be a custom implementation.

In your position I would look for a complete bidding platform.