I have thick mid length hair and tried a mini Mark Hill Shampoo - got two and half washes out of it!!

I've bought full size versions to take with me, plus a full size shampoo and conditioner for my husband and little one to share.

At most airports once you have gone airside there is normally a boots where you can purchase shampoo, luggage will have already been weighed and checked in by then and you can just pop it in your hand luggage.

As you will have passed through security there will be no problem with liquids because you purchased it from inside the airport.

I don't fine I get much use at all out of those miniature bottles. I find it better to take 1 normal size bottle of a 2 in 1.

My hair is short and very fine. I only use a small blob of shampoo as don't need much & I take one of each of the travel size bottles. I usually have some left but as hubby has shaved head he doesn't need it

I don't know how small the bottles are you are taking but I took the small Aussie Moist, shampoo and conditioner on my last trip and have used those Charles Worthington travel size in the past. I have short but thick hair and I certainly had enough for my two week trip.

I use the shampoo bars from Lush they last ages and don't take up much weight or room. There are a couple that are combined shampoo and conditioner.