dilly, what/which service are you gonna provide?. And, what geographical area?
My daily budget is £5 per day (I am a sole trader, 4 extra clicks, jobs @£1.25 'costs per click' is adequate for me), but, clicks only turn into phone calls/bookings IF, and its a big 'if', they like the look of your website, can find what they want quickly (concentration period on looking at sites is. say, just 8 - 10 seconds) and then be bothered to call you (get any landline calls diverted to a mobile number, punters dislike ansafones....)
Adwords express is a whole different ballgame, and waaaaay to expensive for me, is this what you were offered?
I limit my adwords campaign to Norwich, Covering all of Norfolk or East anglia is no my agenda.
DH