Remember what you are paying for is a level of service and in the end results.

I would personally interview multiple brokers and ask the tough questions,

1. How long have you been in business.
2. I would like to see a list of your personal solds in the past year? in my neighborhood?.
3. Can I see your website?
4. What professional designations to you hold?
5. Give me an multiple examples of your marketing such as realtor.com, local media,
6. Do you promote in an extended area and if you do, give me an example.
7. References from your last 6 Sold’s

What I suspect is the cheapest will be limited in the answers from the above.

Real Estate is much more than placing a sign in front.
References :