Toyota Echo 2001?

I need a mechanic who will do the work and not less. I believe my car makes a loud noise when I reach speed off 45 mph. When it idles it sounds sweet and I have been current on oil changes and every few years a tuneup. My questions is what do I tell the mechanic so I don't end up $1000 short and worse off then to begin. Who to go to SW Las Vegas over by Tropicanna and Hwy 215 the Sienna area? Some co-workers suggesterd Gemini Goodyear? Other choices?