I only bought one new piece for Portugal (because I am trying to be good!) and it was this crochet halter dress from Elliatt -- a new brand for me which (don't be shocked) makes super cute dresses.
I paired it with a simple ribbon wrap belt and Marion Parke Lorelei Heeled sandals (available from LGS on ebay -- I promise these are authentic). The fabric on this dress was really luxe and comfortable although rode up a little with walking. It made me appreciate the impact of detailed fabric (lace, crochet etc) on an otherwise simple halter dress. While this dress is no longer available I have some alternatives linked below!
How pretty is that sunset! Nice shot on the iPhone X