I only buy what I love/want to wear, and have many bra and knicker sets in a wide variety of colours, mostly from AP, all with matching suspender belts. I also have corsets, basques, sheer mesh bodysuits, lace bodysuits and a wide variety of stockings too. However, no-one ever requests any of this, they all want just bra and knickers, black or white, in either sheer mesh or lace.
That said, I am so thankful that no-one ever requests a g-string, I hate them, don't own any and would refuse to wear one even if asked to!
If it's an overnight, I sleep in either a silk and lace teddy or a silk and lace camisole with matching French knickers. (Far more appealing than the t-shirt I wear to sleep in when I'm at home!)