This is the Rolleiflex Baby. One of the prettiest cameras ever made. It's smaller and lighter than the standard Rolleiflex cameras - due to its 4cm x 4cm format (other Rolleiflex cameras are 6cm x 6cm) - but still has the ever-popular Xenar lens.
It was built by Rollei for almost 10 years from 1957. It was originally sold for around $135 but its price dropped as the smaller 4x4 format became less popular.
A clean and serviced example today will cost perhaps £200 to £300. Unfortunately it uses 127 format film which is no longer available. Its dedicated and hard-core fans will cut down 120 film ... but this isn't something I'd recommend.
So, sadly, it's a camera destined for display only.