Nobody likes spam, but customers do appreciate occasionally being reminded about what you can do for them. And you can also offer free information, advice, special offers, etc that your customers may be really pleased to hear about. They may even tell their friends.

Offering a newsletter is a great way to build your relationship with your customer, but it's important to follow "best practises". I can advise on this, and will help you set up systems that make it easy for you to keep in touch with all your clients: past, present and future!