If you read any of the histories of the Ukulele, the name Manuel Nunes crops up very quickly as one of the three cabinet makers credited with inventing the Ukulele. Manuel Nunes however, was the only one that went on from a small luthiery shop like the other two, (Augusto Dias and Jose do Espirito Santo), to start a company, (M. Nunes & Sons), in 1910 making Ukuleles. 

After he retired in 1917 his son Julius Nunes, who had taken over as general manager in 1915 after a brief stint on his own, (though I have never seen a Ukulele attributed directly to him?), continued the firm into the 1930's, (though it may be the case that the Southern California Music Co. brought the name in the late teens?)

The company produced mainly Sopranos of varying decoration, along with Concert scale Taropatches, but I have not seen any variations beyond this.

Another son Leonardo Nunes started with the company, (hence Sons), but left in 1914 to start his own company and moved to Los Angeles before 1920. 

I have seen a ukulele dated 1997 made by Richard Nunes, (Manuel's great grandson), and saying it was made by R. Nunes and Daughter of Kahaluu, Oahu, Hawaii. I don't know what happened to this venture?

There is no evidence to show that Manuel Nunes was related to Octaviano João Nunes da Paixão a famous Madeira luthier who died in 1874.