P Leahy has been part of the history, heritage, progress and development of Mosman for over 100 years since its foundation in 1890.
Irish born Patrick ("Paddy") Leahy opened a sales office in Mosman in 1890 to sell land which had been recently subdivided. As the land sale business grew he and his wife Ellen (nee Carroll) took up residence in Mosman and became actively interested in the affairs of the suburb. His popularity and enormous contribution to the area was rewarded when he was elected Mayor in 1904, a position he held until his death in 1909.
Prior to his death, Paddy Leahy had purchased land on the corner of Military Road and Avenue Road and erected his office virtually as it now stands. The building has become Historically and Heritage listed - the workmanship on the cedar staircase alone is a tribute to the tradesmen of the early 1900s.
Paddy's wife Ellen had a brother, Tom Carroll had two sons, Sydney and Dalton (known as "Jack"). Sydney and Jack arrived from New Zealand prior to 1900 and were cared for by Paddy and Ellen Leahy. Sydney joined the business on his return from the 1914-18 war before opening his own business in the City - S.H.Carroll and Co. Ellen carried on the business with her nephew, Jack, who would remain with the firm throughout his life.
Ellen was responsible for the erection of many buildings in Mosman, the first of which was a cottage at the northern end of Balmoral (Edwards Beach) where she resided for her lifetime. She originally purchased the land for $120 to the high-water mark. Apart from her many business activities, Ellen was better known for the tireless effort she devoted to charities, in particular the Mosman Red Cross where she was the foundation President, and the Mater Hospital at North Sydney. She was awarded the M.B.E. for her efforts and continued this charity work until 1940 when she died at the grand old age of 87 years.
Meanwhile the Real Estate company continued to grow with the able back-up and support from her nephew Jack. Jack Carroll  served two terms as an Alderman of Mosman Council and was Mayor in 1934. Following the death of Ellen, Jack managed the ever-expanding business and in 1945 was joined by his son, Bill. Jack had a life long interest in the history of Mosman and in 1955 he began to devote more of his time to write the history of Mosman. He left a legacy to the suburb of Mosman in his books. He is also remembered by "Carroll's Lookout " at the foot of Edwards Bay Road adjoining where he lived, named by Mosman Council in his honour, by the collection of historical papers and pictures now based in Mosman Library and by the mast of the original H.M.A.S. Sydney at Bradley's Head, for which he was responsible, being Mayor at the time. Throughout these many years of collecting and preserving documents and photographs relating to Mosman's history, Jack was tirelessly assisted by his wife, Eileen who also spent considerable hours each day supporting and furthering the cause of many charities.
And so today, a fourth generation, Bill and Judy's daughter Edwina and son Rowan, continue the business. With the advent of corporate takeovers and franchised operations, it is doubtful whether there is any other suburban Real Estate firm which can claim family ownership and involvement for over 110 continuous years beginning in 1890.
There are many clients of P.Leahy Pty. Ltd. whose properties have been managed since 1903 and continued through generations. Records show interesting features of business in the earlier days of the company - namely simplicity. Since 1912, records of sales and Council revenues etc. indicate amazing prices which are still relative to inflation trends. Average residential blocks of land on Balmoral Slopes $100, Waterfront $150. The same blocks are now bringing over $5,000,000.