Not really sure I understand your question fully, but the only price that would increase is your ad spend - having more keywords increases your ad exposure, your clicks, and thus your ad spend. Aside from that, adding more keywords doesn't directly impact the amount you spend per keyword. We could go much more in depth about the impact of adding keyword phrases to your campaign that in turn impact your quality score > which in turn impacts the max CPC, but I think that's a bit over the top for your question! thank you TheAdwordsProfessor.com