For an accurate quote all you need to do is supply the following 3 bits of information:
1) How long will you need me? (Approximately)
2) Where is the Venue located?
3) What are your requirements?
2) "What areas do you cover?"
As a full time professional, I happily cover most of the UK and should I not be available for the date you require I will always suggest other experienced professional colleagues - so there will always be someone to fulfill your requirements.
3) "Any Additonal Costs?"
The fee you are quoted will always be the correct full fee. No additional costs.