These aircraft companies are known chiefly for their trainer aircraft, some of which are still flying around to this day!
The Azionara Vercellese Industrie Aeronautiche produced aircraft designed by Francis Lombardi and was based in Vercelli. The FL.3 was designed before WWII and was used for training purposes by the Regia Aeronautica, sometimes for glider training by removing the propeller. AVIA continued FL.3 production after WWII. RS Models released a trio of very high quality 1/72 injection kits of this lightweight trainer. It is a delightful little kit, with fine detail and lovely crisp moulding. Italiankits have also produced a nice looking 1/48th resin kit. Ali d'Italia printed a neat mini-reference guide for this aircraft.
The Compagnia Nazionale Aeronautica was founded in 1920 by Count G. Bonmarche. The PM.1, a high wing monoplane trainer aircraft, was designed by students of the Instituto di Construzioni Aeronautische del Regio Politecnico di Milano in 1938. Only a small number were built and none survived the war. Post war it was revived as the Macchi MB.308 with a tricycle undercarriage and an enlarged tailplane. The SEM Models 1/72 kit looked fine in the box with nicely cast resin pieces but production has been suspended.
The Nardi brothers set up their company in 1932 and quickly gained a reputation for design excellence, especially the FN.305 which, due to space limitations, was assembled by Piaggio. The 'mini' Ali d'Italia reference booklet shows just how adaptable and capable this aircraft was. As well as the familiar two seat trainer, there was a bewildering variety of other types built: racing, record and single-seat versions as well. The old 1/72 Legato resin kit for a single seat version was disappointing but Azur produced a much better quality 1/72 injection moulded kit of the two seater. Special Hobby also issued a series of fine 1/48 injection moulded kits giving the modeller a choice of foreign as well as Italian machines. The LF Models 1/48 resin kits of the FN.305, FN.315 & FN.316 subtypes are interesting but they do not have the same finesse. Aerofan # 97 has an in depth article on the FN.315.
The Societa Anonima Industrie Meccaniche Aeronautiche Navali was established in 1934 in Lido di Roma and was a member of the Caproni group of companies. They only made a small number of aircraft and their 200 and 202 designs are their most well known. The SAIMAN 200 was a small biplane trainer that was also used for commuication. Choroszy Modelbud do a delicate 1/72 resin kit of this aircraft and JACH Models released a good quality 1/72 injection moulded kit. It has since reappeared as a AZ Models kit with more decal options. The SAIMAN 202 was a side by side two-seat low wing monoplane design with an enclosed cabin. Its similarity to the Percival Proctor trainer aircraft is worth noting. It was used mainly for liaison during WWII and production continued after the war. The 204 was a four seater version with a larger canopy and long engine cowl to fit the larger six cylinder engine. Only Kora Models do a 202 kit, a series of 1/72 limited-run injection moulded kits all made with the same tooling and with a resin cast canopy. Subjects covered are Italian civil & military options as well as German, Hungarian and Croatian aircraft. It has also been doubled up with the 1/72 AZ Models Bf109 G-6 kit in Swiss, ANR and captured RAF themed boxings. The model is rather crude, with most parts requiring refinement. Italiankits have a 1/48 resin kit of this aircraft in the works.