Skip Tracing fees too much?

[Alesha Bracey]

I'm a wholesaler in Baltimore, MD. The problem I'm running into is I'm finding these empty houses however when I look on the SDAT The mailing address is the same as the empty house. Someone recommended a skip tracer? I researched 2  that I came across who were EXTREMELY expensive. One wanted 30% of the each deal. I'm new to the game and I'm wasn't sure if I was being bamboozled.