Running hot

I own a 99 Mercury Tracer with 88k miles. Car is running hot. 4 mechanics, 4 different causes. When the car is in park running for hours on end (according to mechanics), gauge goes up to half way but stops.

Highway driving makes the temp gauge rise. I spoted small amount of smoke in front left of the engine (standing in front near where the water pump is) but can not see a leak.

I have been told it was the fan, the theromostat, the water pump & head gasket. I do not have milky oil nor white smoke which would both be indicators of head gasket.
My water pump is not rattling and when the cap is off the radiator, I can see the water circulating & the thermostat has been changed.

Any ideas am nearly out of funds & will be without a job if I can't get thing fixed soon. :(