The Villa Kapantzis was built on what used to be a seafront plot of 4,000 sq. m. At the time the west side was visible only from the sea. The mansion essentially comprises two buildings, the main residence and the tower, which are linked to each other. The main building (16.50 m. wide, 19.00 m. long and 18.00 m. high) includes three storeys (a semi-basement, an elevated ground floor and a first floor) and an attic. The tower (4.40 m. wide and 6.60 m long) is four-storeyed and the part above the ground floor is open. The main entrance is on the side facing Vasilissis Olgas Street.
The architecture displays overt Central European influences. Essential features include the complex volumes, a multi-level roof with steep slopes and the tall, rectangular tower. The decoration of the building's interior is rich and varied, thus differentiating each room. The floors are of different materials (marble in the entrances, parquet flooring in the reception areas and wooden boards in the remaining areas), as are the doors, windows and storeys. Wood-carved ornaments and wainscot panelling distinguishes the areas and rooms. The double-flight staircase is of monumental character and is decorated with wooden veneer, elaborate balustrade and lighting. The ceilings of the ground and first floor are painted, apart from the central areas. Unfortunately, most of them have been destroyed, except for some samples, on the basis of which an attempt has been made to restore the compositions, wherever the necessary evidence was available.