I personally think $200 is a fair (not excellent, but fair) price for a secondhand Nina in very good condition with no mods and complete with full stock, if she were to be listed on eBay or something. Nina is just so hard to find. If she were to be listed in the B/S/T forum here on DM, $150-180 would be a more reasonable price. (It seems common practice that items cost ~10-20% lower, or more, here on DM relative to comparable eBay listings.)
So no, I don't think you're misleading your friend on the price.
Whoever is trading Nina for $200 is just getting the maximum amount of money for her. What really matters is how much your friend wants the doll, knowing that a "dolly collector to fellow dolly collector" personal transaction price, outside of a commercial marketplace like eBay or Etsy, would be like $150-180. She might ask for Nina and an extra $20-50.
So no, I don't think you're misleading your friend on the price.
Whoever is trading Nina for $200 is just getting the maximum amount of money for her. What really matters is how much your friend wants the doll, knowing that a "dolly collector to fellow dolly collector" personal transaction price, outside of a commercial marketplace like eBay or Etsy, would be like $150-180. She might ask for Nina and an extra $20-50.