I had mine done 11yrs ago with House of Colour. It was expensive at around £200 then, I expect it is more expensive now. Along with upselling of makeup and kettlewell clothes (which I didn't buy into). A simple process of colour draping, holding up fabric shades to see which colours make your skin and eyes pop.
I remember looking at the colour wheel and thinking, anything but Autumn, disliked the sludgy browns, khaki and mustard. I loved the winter colours and wore them constantly, lots of black, blues and purples. So was after a confirmation that i was right but no, of course I'm a warm and deep Autumn.
I've fully embraced it and strictly only buy clothing in my shades, I love how simple it is to mix and match all my clothes. I have a full rainbow in my wardrobe compared to the monotone old clothing. All the white gold and silver jewellery, black shoes, coats and bags have been replaced with tan shoes and bags, camel coloured coats and gold jewellery and they all work with dark navy or khaki jeans and green/ beige/ orange/ mustard/ red tops. Shopping is easy as first I look by size and colour then material, style and fit. My hair colour is now brown with honey ombre highlights, I can see why the cool plum hair colour that I loved washed me out. Makeup is another thing, warm shades instead of cool, brown or green eyeliner instead of black etc.
So, yes it has transformed my personal style and I would 100% recommend it.