Luggage

Try to stick with a 21". Not only because you can carry it on the plane but because it is challenging to deal with a bag larger than that in trains and on buses. Add to that a day pack, like Rick Steve's Civita bag for add'l capacity. All you need are 3 pair of slacks and/or jeans, 3 or 4 tops, a couple of layering pieces for cold weather (a pullover and a cardigan), 2 pair of shoes and a light coat. My rollaboard weighs in at about 23-24 lbs. That's about all I can lift over my head or carry up a staircase in a train station. I can't tell you how many women I saw that had huge suitcases they couldn't lift on and off a train, and were totally unprepared to carry them up and down staircases between train platforms. Yes you will need to hand wash a lot, but it beats struggling with luggage. The day pack should not be filled to the Max so you can accumulate a few items. You can also safely ship home for UPS stores all over Italy, so don't feel like you have to carry everything for many weeks. See Rick Steve's packing list for women. It's helpful in trimming down to the essentials.

I agree, take the 21" and an additional piece as a daybag (I use the Civitas). If you plan to not check any luggage, keep in mind that some European airports (like Amsterdam) are careful about carryon luggage weight (I think there's a 12 kilo limit; mine was 16 and I had to repack at the airport to distribute the weight between the 21" and the daybag).

Go with a carry-on. Add a duffel bag when you get there (under 10 euro from a street vendor) and check it on the way home (put all your breakables in your carry-on, but no liquids).

We bought the 21" Rick Steves rolling bag plus the Veloce Shoulder Bag (can also be used as a backpack), which fits nicely over the carry-on. Fit everything needed for an 18 day trip in it. Both of us took that combination and it was great. I put a large light weight zippered bag folded up in the bottom in case I bought things. That way you can check the carry-on and carry on the zippered bag (or vice versa) for your return trip. Friends just found a zippered bag inexpensively at a market to bring things home in. Follow the sites for packing light and stick to it. There is much you will not need or ever use. I bought a purse once there, not taking one with me.

I agree w previous postings. you can always hit a self serve laundromat, too, if you are somewhere for a couple of days. I brought loads of very thin tank tops that dried quickly and took little space, then layered shirts over them.
My daughter and I each got Skymiles memberships when we bought our Delta tickets to ITALY and were pleased to find we could each check one bag free when we came home. We checked our carry-on suitcases and then didn't have too much to mess with. You still have to collect and rescheck those bags when you get to US, if you have connecting flight, but we found it pretty easy in Atlanta.

We travel with a 21" RS rolling bag and check them. We each have a backpack, one of which is the equivalent of the 21" bag without wheels or "bones", and we carry them on. One has meds, one clothes change, and other things we want with us but won't need in flight, and the other has things we will want on the plane like Kindles and snacks. We have the fold-flat bags that work for laundry bags or a carry-on if absolutely necessary. Last trip of 21 days we did buy a nice small carry-on bag at the end as we decided to bring back lots of Paris chocolates for hostess gifts for our daughter's baby shower...a sacrifice worth making! I don't take a purse...we have two Veloce guide bags and use them every day and feel they keep our belongings very secure. There's no point in our trying to look like locals...we don't and never will, and we can identify all the other tourists, too. So we go for what works. We've made the early mistakes of too many big bags and won't ever do that again. It's kind of a fun challenge now to see how light we can pack.

21" is really cumbersome on the train, especially on the crowded the Leonardo Express into Rome.