What are some good ways to get free/cheap advertising?

[Rosemary P]

As well as word of mouth that's been mentioned, think about press coverage. Do you have a particular story to tell about your business? Has something newsworthy happened recently? If you have a story - not a blatant plug for your business - contact your local newspapers and ask them if they'd be interested in running it.

I helped a business in our area with their story and their telephone didn't stop ringing for the next 72 hours.

Presumably you have signage on your vehicle(s). While you're driving, you're advertising and when you're parked prominently outside your customer's premises, other people can ask them what they think of the work you're doing.

Good luck!