I dont own smart clothes but find looking tidy always gives a good impression.
I always were jeans or combats and tshirts/rugby shirts/loose fitting shirts, even to work.
My psych usually puts in letters that I was smartly dressed, even though the clothes I listed above arent what I would class as smart, so its possible to look it without actually wearing sterotypical smart clothes, if that makes any sense?
Like my nurse used to comment I was always smartly dressed which I took to mean my clothes were clean, looked liked theyd been ironed (I dont iron anything), id washed and washed my hair and things...
Might not be everyones idea of smart but thats what it means to me.