Two small Roman tours that I remember best are one of the Vatican and a walking "foodie" tour in Trastevere.
There were only six of us on the Vatican tour. The docent was a lovely young lady, Canadian I think. She made sure to honor our special request to see the Papal apartments from my wife's family.
Context Travel provided that tour.
Of the Roman "foodie" tours that we've taken, I enjoyed the walking tour of Trastevere the best. Man, do I love porchetta. That tour was provided by
Eating Italy Food Tours.
Enjoy your trip to Italy. Eat everything and drink lots of wine. My wife likes the Aperol spritzes.