I haven't had a chance to catch up on everything here, but did notice someone talking about the 2.5 gal bags.
On our last couple trips I used a huge XXL Hefty ziploc bags (I think they are like 13 gallon or something like that) as a laundry bag. It's sturdy enough to stand up in the closet, so you can just throw your dirty clothes in. Then when you go home, if you push all the air out you can compress your dirty clothes into a small, compact bundle. And more importantly, the ziploc keeps your dirty clothes from stinking up your clean clothes on the way home.
I still haven't unpacked from the last trip, but I want to work on that tonight. At least I have all day Saturday to finish up before we fly out on Sunday.
Wendy