Do you mind if I keep these here?
¿Le importa que las guarde aquí? Isn't this right for "Do you mind if I keep these (beers) here? Gracias.
No, no problem. But where is the bottle opener?
No, no hay problema. Pero dónde está la abrebotella?
¡No hay de qué!
I would think that it would be ¿Te importa...? I wouldn't trust anyone, but a friend (and probably not one of them) with beer.