Just so you know I created my yelp page it was free I picked the 5 cities locally I serve and I did about 10-15 jobs a month for 2 years with out paying out a dime.
That's when I decided to go for the minimum 500 search for $300 a month they had a guy come shot a video for me included in the price they used smart shoot I recommend them the guy who did mine. He was really good.
Since I started paying I went to 20-30 jobs a month.
Usually Yelp receives money from the top. 2-3 advertisers in a area they place you on all competitors pages in your area.
Most people on Yelp don't pay a thing.
Go to Yelp.com and create your Free account. Any site that lets you have a free listing where you can link your website to is gold.