Hours in now, I have researched attraction tickets (oops - you really need to book a lot of these in advance), transportation passes, Roma Pass combo ticket, walking times, entry points, metro stops, restaurants, and I'm sure more. See The Basics of Visiting Rome for all the details I found out.
So many options for tickets, passes, combos, availability, best times to visit! I had so many browser tabs open it was almost hard to keep track of it all. Thankfully the hotel was sorted a while ago - really swanky using points!! I'm so excited!
I'm pretty happy with the prices I got. I ultimately decided to book everything separately. The main hit being the extra cost of the hosted ticket (€52 from Headout) to the Vatican since I waited too long and the official direct tickets (from Biglietteria Musei Vaticani, half the price of what I paid) were all sold out so my options were getting pretty pricey. I booked the Vatican without special access to the Basilica. I'll just hope the line isn't too long, or I MIGHT book the €7 reserved time that supposedly has a dedicated entrance.
I decided to skip the various combo and transportation passes and was able to book the Colosseum directly from the official website for €18 which will include the Roman Forum and Palatine Hill.
So what started out a potentially over €150+ for a tour to include the Vatican, Basilica, and Colosseum, I will now spend €70 to see all of them. Much better. If you keep at it, read reviews, do various Google searches read forums, etc., you will come across the better options! Don't give up!
Transportation around town, to and from the airport, restaurants and free drinking water throughout the city! - Check it all out in my post The Basics of Visiting Rome.
Also adding to the list will be a visit to the Pantheon (just the oustide this time), the Trevi fountain, Spanish Steps, Capuchin Monk Crypt, pasta at Pastaficio, and definitely my favorite tiramisu at Pompi!