premise: The Probert-Price Collection is a collection of items from the Probert-Price estate, primarily hundreds of vintage dresses which belonged to Renee Probert-Price, original It girl and well-known London socialite of her time (1917-2013). Renee died in 2013 aged 96, and left over 300 dresses, hats, furs, shoes and handbags dating from the 1930s and 1980s to her great niece and goddaughter.
hypothesis: Renee Probert-Price  left at least 50 hats to her great niece and goddaughter.
reason: It's not clear how many hats exactly she left, just that she left over 300 items in total of various categories (assuming I'm reading the text correctly), it's difficult because the text phrases the amount somewhat ambiguously to just say over 300.