Hi guys/girls!

Pretty much as the title says - can I upgrade with cash on my flight from LAS-LAX at the Airport, or..?

Also, how much will this upgrade cost? I've never tried upgrading with AA - I normally always fly BA, so can I get Tier points on the upgrade credited to my BAEC - if so, how many?

I am not really in it for the service in-flight since its only a 40-50min hop, moreover I'm looking for the extra Tier points .

Looking forward to your replies.

Marc