I have found, by far the best way to go, is to tele-market prospective clients in your particular target field, be it branding or exclusively interiors.
From being involved in this for the last 8 years for clients, and the last 22 years on my own businesses, I have found that this method of approach NEVER loses its effectiveness, particularly when the tele-marketer is well-spoken and professional at all times.
We operate this service which was originally bespoke to the financial sector but now offers every industry and profession the opportunity to have quality 'callers' working from their particular office. This is London-based, only, currently.
If anyone has any questions, please do not hesitate to get in touch.