The two storey brick mansion house, Prospect, was erected in 1855 for Thomas Must, a wealthy merchant who in 1845 journeyed form Sydney to establish a Portland branch of the merchant firm, 'Must and Flower'. The symmetrical, once distinctive Italianate style house with open single storey verandah, single storey kitchen wing and stables, has been considerably defaced by later alteration.
Prospect is an early Portland mansion house which stands today as testimomy to the enduring business acumen of influential pioneer merchant Thomas Must. The original Italianate character of the residence has been all but obliterated, and the principal interest is in the long association with Thomas Must who resided at Prospect for 53 years (1852-1905). The fenestration patterns have been altered and the single storey verandah enclosed in an attempt to create a pseudo-regency atmosphere.
The integrity of Prospect is extremely low. The house has been converted as a special accommodation rest home for elderly people, the internal layout and fittings altered, and the interior redecorated. The stables have been extended as accommodation for the proprietor.