1989 Mercury Tracer wont star and smells like fuel

1989 Mercury Tracer Mileage: 132,000. I towed my car to a mechanic because it wouldn't start when I was leaving work one day. He said that it needed a $300 tune-up. I thought that was high so I had another mechanic tow it and look at it. He said that he cleaned the fuel line and changed the spark plugs because they were "fouled." When I went to pick it up, they said that it smelled like fuel when they tried to start it and the plugs were "fouled" again. I haven't had my car in two weeks please tell me what they should be looking at. Thank you.