Booking drivers vs. driver/guides vs. escorts (not THAT type!) vs. licensed guides

[bigwally]

What should I expect from my private driver/guide and his company when it comes to the information that will be provided on the sights we see?

 

Take the Forum in Rome for example, where licensed tour guides are not required. Would the driver/guide (with a smaller group) or tour escort (with a larger group) be expected to escort us through the Forum, describing what we are seeing. Or would he simply let us off the van/mini-bus to find our own way around?

 

Now take the Coliseum, where licensed tour guides ARE required. Should we expect the company we've contracted to arrange for a guide (at extra cost naturally) to meet us and escort us in? Would we contract that ourselves? Or would we simply buy tickets for the Coliseum and, again, find our own way round.

 

I'm just trying to get an idea of what information we will receive on a basic tour, what we'd need to pay extra for (licensed guides and admissions), and where we will need to find our own way around.

 

While talking about the Coliseum, I am very concerned about maximizing our time in Rome. Would you expect the tour operator be able to arrange pre-purchased admissions for most of the important sights for us, so that we aren't waiting in long lines?