Resale Value
NRFB dolls command higher prices in the collectibles market because they are untouched. Older dolls from the 1960s command the highest prices because of the limited number of NRFB dolls still around from that era.
Box Condition
NRFB implies that a box has not been opened, but not that it is in mint condition. Shelf wear or dents in the plastic can reduce resale value unless it is a rare item.
Pink Box
Dolls manufactured for the toy market are known as "pink box" items, based on their bright pink packaging. Even if NRFB, pink box dolls tend to have minimal resale value unless the doll is hard to find or is unique in some way.
Limited Editions
Dolls produced in limited quantities and aimed at professional collectors are usually what collectors seek in NRFB condition. These dolls are not meant to be be played with and often include decorative boxes for collectors to use in their NRFB displays.
NRFB vs. Mint
Mint condition means the box has been opened but the doll is pristine. A doll in mint condition may still be valuable, depending on its age, uniqueness and manufacturing numbers.