I'm a bit of a weird shape, I'm a size 18-ish round the bum/tum/hips but I have really chunky legs, my calves are quite fat big.
When I try a size 18 jeans on, they're ok round the waist but really tight on my legs, like leggings 
When i try a size 20-22 they're ok on my legs but super baggy round the waist and hips.