A blast from the past:
Hellenic Coast Guard (AU) roots go back in 1835, when the Port Police was established (under Ministry of Naval Affaires). However, sea protection/surveillance remained responsibility of Royal Hellenic Navy until 1919, when the the sea branch of Port Police was created. In 1923 all nesseceary personnel training was completed and duties of Sea Protection Command of Port Police were ready and became state law. The public name of the service was "Harbour Corps" (Λιμενικό Σώμα). Several ships were transefered from Navy, mostly obsolete "Atmodromon" types, built in 1880-1890. Hydroplanes from Naval Aviation stock were also transfered. The most significant transfer were the Maritime Fund for Sea Protection from RHN. In 1929 first pursuit boats appeared, designed by Alkiviades Zeis Shipyard. The smaller 7.5m launches were transfered by large vessels on davits, while larger 11m and 14.8m were based on ports near smugglers passage. Armament was usually suplus WW1 Swarzlose machine guns (6.5X54mm) or Lewis guns for hydroplanes. In early 1930's large seaplanes were purschased, Dornier Do16 and Blackburn/SHAF Seagull (based on Iris/Perth design). Some new patrol vessels entered service in lates 1920's and during 1930's.
Zeis 7.5m (1929 design)
7.5m X 2m X 0,7m, Ford I4 flathead engine 60hp (later V8 flathead 85hp), 25-30kn, two Swarzlose machine guns (one rear, one side opposite of driver)
Zeis 14.8m (1934 design)
14.8m X 3.8m X 1m, twin modified aero engines of 300-420hp, >30kn, three Swarzlose machine guns (one rear, one double mount front).
The 11m was for coastal patrol (beam 3.2m, draught 0.8m), twin Lycoming V8 marine engines, speed about 21-22kn, while the 14.8m led to the succesful Zeis Light Torpedo Boat of 1937.