For anyone looking to visit Valetta or indeed Malta, I highly recommend Tonio's apartment.
We looked at accommodation in Valetta and found it to be small and v. Expensive.
Birgu is a mere 10 min ferry ride to Valetta, which provides further access to the reat of Malta, via tours/bus.
The apartment has beautiful views over the harbour and historic Birgu has lots to offer. Would recommend you explore the area and try some of the great restaurants.
Our host was there to meet us and was very welcoming. He's clearly very proud of his area and provided some lovely personal touches which made our stay feel like a home from home.
Apartment was spacious and clean, with lots of storage and a cute balcony for people watching.