The Beech 1900 commuter aircraft shares many components with the Super King Air series. Essentially it is a stretched Beech 200 with a higher cabin and further spaced cabin windows.
The Starship is a twin turboprop aircraft with pusher props in canard configuration. It has no single vertical stabiliser, but two vertical surfaces at the wingtips acting as vertical stabilisers. This distinguishes the aircraft the most from the Piaggio Avanti.
The Beechjet, and the MU-300 from which it was developed, is a small business jet that can particularly recognised by its typical cockpit window configuration: the frame is diagonal but titled ninety degrees compared to "standard". The cabin windows are oval.
Beechcraft 50 Twin Bonanza
Although bearing the name Bonanza the Beech 50 is bigger than the true twin Bonanzas, the Travel Air and Baron. The Twin Bonanza is similar to the smaller siblings, with as main recognition point the main gear that retracts forward in the nacelles. The vertical stabiliser is always non-swept.
The Beech 99 fifteen-seat commuter aircraft is clearly a descendant of the Beech 65 Queen Air. It is basically a stretched version with the turboprop engines of the King Air and a much longer nose. The Beech 99 retains the square cabin windows of the Queen Air.
Based on the King Air 90 and King Air 100 Beechcraft developed T-tailed versions. These have the same characteristics as the low tail King Airs, such as cockpit windows, round cabin windows, engine nacelles and landing gear, but with a T-tail. Especially the cabin windows make the distinction between a T-tail King Air and a Piper Cheyenne III easy.
The Beechcraft Queen Air has low wings and low horizontal stabilisers, with two piston engines and single wheels on each undercarriage leg. Compared to the Piper Navajo, which has the same general configuration, it has smaller square cabin windows and the main gear retracts forward into the nacelles instead of sideways in the wing. Also look at the cabin windows. The King Air (90/100) is basically a turboprop version of the Queen Air.
Beechcraft T-34 (Turbo) Mentor
Beechcraft made a primary training aircraft based on the Bonanza private aircraft. Especially landing gear with triangular main landing gear doors is a key feature copied from the Bonanza, as is the nose of the piston powered version. The fuselage has a tandem canopy, with the student and instructor pilot sitting at the same level. The turboprop version is shown here.
The Beechcraft T-6 is a development of the Pilatus PC-9, and shares a lot of its external appearance. The T-6 has a smaller dorsal fin though, a small ventral fin and a three-piece canopy.
Beechcraft Travel Air/Baron
Thanks to being the twin development of the Bonanza the Travel Air and Baron retain certain elements of the single engine predecessor. Most obvious are the triangular main gear doors, that are typical compared to other small twins. Also the cabin windows are similar.