I have the travel toiletries set from Kitsch, and I like them. It comes with little decanting tools to make them easier to fill. I moved on to bar shampoo and conditioner though to reduce my liquids. I recently bought the toothpaste container from Matador, but I haven't used it for travel yet.

Contact cases are great for things like moisturizer, foundation, primer, eye cream!! I especially liked it for foundation because I know I use no more than 1 full pump a day so I just count the pumps for how many days I'm gone.

For something that needs a little more volume I buy little jars for $1 at target but I've also saved anything that comes in a jar or tub such as lip scrubs, eye cream, lip masks. I hang onto them after they are used up.

For shampoo I bought the little 3oz travel squeeze bottles and hang onto them. I use them up when I get home and save it for my next trip.

Also waiting for a good answer here. I usually end up buying those small reusable bottles then decanting from my usual product. But then they're usually so hard to clean out to reuse with another product!

I think i saw this tip from heronebag subbredit, but I've been using lip gloss tubes that I bought off of Amazon for all of my toiletries. It includes serums (pretty runny) and creams!