I always switch my makeup between seasons and the change between Summer and Autumn, is always the most drastic. As a sufferer of dry skin, my base products can be the hardest to find, but for A/W, when I need something a little heavier, but just as hydrating I have three foundations that I am truly faithful to.
Nars Sheer Glow is a foundation I wanted to try for years, I think this was mainly due to it's cult status and the fact that so many of the beauty bloggers I follow had raved about it at some point. I finally picked up a bottle in 2015 and was colour matched to the shade 'Mont Blanc'. 
This is a light/medium coverage foundation, which covers minor blemishes, scarring and any redness with ease, so don't be fooled by the 'sheer' in it's name. The hydrating formula is perfect for anyone with dry/normal skin or anyone who suffers from dull skin and wants a little bit of radiance to their complexion.
I love that this perfects my skin, while still leaving my makeup looking totally natural and fresh, and it has real staying power, there's rarely a need for a touch up when I'm wearing this.
Yes, it's a little on the pricey side, and you do have to purchase the pump separately... but it's definitely worth it.

Illamasqua Skin Base is the foundation I have repurchased countless times for years and years, and I still love it as much as the first time I tried it. I wear shade '07', which is the perfect colour match for my skin tone. 
This is a medium/full coverage foundation, which despite being heavy duty enough to cover any blemish, still manages to feel super lightweight on the skin. It contains Vitamins C and E, so softens and hydrates the skin while you wear it, and feels incredibly comfortable even when built up to full coverage for evening wear.
It's a really long lasting base, which all of the products I wear on top, adhere to perfectly. My skin always looks flawless, glowy and healthy when I wear this and although I've heard people mention that it's not good for really dry skin, I find it works perfectly for me, with or without a primer.

YSL Touche Eclat Le Teint is my real go-to base at the moment. I have it in shade 'BR30', which admittedly is a little too dark for me, but thanks to the formula and consistency of the foundation, I'm able to make it work for when I want to look a little bronzer than I am naturally. When I repurchase, I'm going to be colour matched again for a slightly lighter shade.
This is an upgraded version of the original Touche Eclat foundation, which promises to give better coverage and more of a fresh faced glow without looking any heavier, and it really does the trick. 
It masks any unevenness in my complexion, disguises any redness and covers my blemishes. I buff this into my skin with a foundation brush and my skin is left looking almost airbrushed. The finish of the foundation feels matte, but to the eye, it adds a really natural glow to the skin. 

Which high end products do you think are worth paying a little (or a lot) extra for?
         

        
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