You may require a website that you will want to update yourself on a regular basis or a newsletter facility to send out regular mail shots. Cost will obviously depend on what you need but here is a small list of some features that you could have:

Online Contact Form : Enables clients to write a enquiry on your website that gets sent to your email address.

Newsletter Facility : Clients will be able to register for your newsletter on your website, which you can send them.

Content Management System : Update your website yourself !

Register Page : Lets clients register for your services on your website

Online Chat Facility : Communicate face to face with you clients from your website.