Your customer does not want to be kept in the dark. At the very least, check in at the end of the day giving simple and quick updates regarding your progress. Keep your customer in the loop but don’t resort to psycho dialing them. Once a day is fine unless you have something that needs to be done that was not originally spoken about and could cause the total job to be higher.
This is effectively a part of your marketing strategy. Your customers should have been wooed enough that their need for your services last for the next three to five years. Also, the referral given to their friends and family should last well beyond that. How do you do that? Leave an impression, not just in the immediate work but by using other long lasting strategies.
First you will want to send a handwritten thank-you note just days after the service is complete. Next, you could give a phone call asking if they are still satisfied with your work. This is hard but important. You need to be willing to listen to the customer if they are dissatisfied and be prepared to offer a solution. These two should be done within the first week of completed service. You could use the next week to deliver their warranty but I would suggest that being a part of your final signing off on the job. Finally, you will need to send non-promotional follow-up letters to each customer at the three month, six month, one year, 18 month, two year, three year, four year and five year anniversary of the repair.