Don't need that. 1-2 a week is enough for me.

Is it possible to limit the searches per keyword and get more credit for other keywords.

Example:
Keyword is mobil + desktop x 30 days = 60 searches

In my case I only need 2 searches per week:
mobil + desktop x 8 = 16 searches.

If that works, that is a great deal. If not, I would have to stay with xovi who offer exactly that already.