Questions on Taxis in Colon.Panama

Trawling the internet I have come across various prices for the hire of Taxis,

Examples $8 per hour not sure if it is for per taxi , or per person.

Same $30 to $45 for about 3 hours. Per taxi? per person?

A definitive answer would be welcomed, I do realise that taxis are negotiable.

Taxi 3 hours for 2 or 4 people to visit locks (no museum) & Fort San Lorenzo.

:confused::confused::confused:

Thank you.

Also I note that there are SET taxis whose drivers are like guides, not really bothered to hear a commentary. There are also yellow taxis, are these cheaper than SETs