It is common to need your ads shown only in business hours, the above video shows how to do this.
What it doesn’t show in the last part is applying bid adjustments to certain days where you receive more/less enquiries. Providing you setup conversion tracking correctly, you will be able to see this data in the dimensions tab – if you have a day where you regularly have more conversions than another, then clicks are more valuable on that day – apply a bid adjustment.