Here are some things to think about.....

What is your current target market? Where are you looking to expand?

If you have to, how much are you willing to pay?

What types of advertising are you currently doing?

Are you willing to partner with oter like companies selling similar products or services? Sharing profits?

Possible brochures? Can be relatively inexpensive

Where are you looking to expand from your current product line?

Do you install or just sell items?

....These questions might help to direct you towards a specific form of advertising and promotion to fit the needs of your company.