Especially at this time of year,it would be a good idea to offer gift vouchers.
Do you make gift vouchers available as part of your marketing, £25.00 off jobs to the value of £100.00 or so send out to past and prospect customers or even bought as gifts for family and friends.
Virgin do it with wine if ever you receive something from Amazon you will probably get a voucher in their from them and when you register and log in it goes straight away against a pack of wine valued at £120.00 or £140.00 tempting you to purchase.
Great idea that should be employed elsewhere, cut out the likes of Groupon and keep it in-house.