| Koser | B. | 256 Stirling Street, Perth | Overland | 7546 | Metro Private Car | 1925-26 |
| Koser | B. | 256 Stirling Street, Perth | Overland | 7546 | Metro Private Car | 1926-27 |
| Koser | B. | 256 Stirling Street, Perth | Overland | 7546 | Metro Private Car | 1927-28 |
| Koser | R. | 162 Brisbane Street, Perth | Harley Davidson & Sidecar | 974 | Metro Motorcycle | 1922-23 |
| Koster Webster | - | Kalamunda | Reo Bus | DR ● 59 | Darling Range Road Board | 1927-28 |
| Kostera & Webster | - | Kalamunda | Austin | DR ● 7 | Darling Range Road Board | 1926-27 |
| Kostera & Webster | - | Kalamunda | Studebaker | DR ● 8 | Darling Range Road Board | 1926-27 |
| Kostera & Webster | - | Kalamunda | Reo Bus | DR ● 24 | Darling Range Road Board | 1926-27 |
| Kostera & Webster | - | Kalamunda | Federal Bus | DR ● 32 | Darling Range Road Board | 1926-27 |
| Kostera & Webster | - | Kalamunda | Federal Bus | DR ● 59 | Darling Range Road Board | 1926-27 |
| Kostera and Webster | - | Kalamunda | Austin | DR ● 7 | Darling Range Road Board | 1927-28 |
| Kostera and Webster | - | Kalamunda | Studebaker | DR ● 8 | Darling Range Road Board | 1927-28 |
| Kostera and Webster | - | Kalamunda | Reo Bus | DR ● 24 | Darling Range Road Board | 1927-28 |
| Kostera and Webster | - | Maida Vale | Federal Bus | DR ● 32 | Darling Range Road Board | 1927-28 |
| Kosterich | F. B. | Ballidu | Ford Truck | WB ● 164 | Wongan-Ballidu Road Board | 1927-28 |
| Kosterick | J. | 537 Wellington Street, Perth | Overland | 7294 | Metro Private Car | 1925-26 |
| Kostos | George | 198 William Street, Perth | Chevrolet Wagon | 2970 | Metro Private Car | 1927-28 |
| Kott | M. | C.T.A. Chambers, Perth | Bean | 684 | Metro Private Car | 1922-23 |
| Kott | M. | C.T.A. Chambers, Perth | Bean | 684 | Metro Private Car | 1923-24 |
| Kott | M. | 56 Victoria avenue, Claremont | Hudson | 9923 | Metro Private Car | 1926-27 |
| Kott | Max | 692 Beaufort Street, Mount Lawley | Overland | 4665 | Metro Private Car | 1923-24 |
| Kott | Max | 692 Beanfort Street, Mount Lawley | Oakland | 4665 | Metro Private Car | 1924-25 |
| Kott | Max | 692 Beaufort Street, Mount Lawley | Oakland | 4665 | Metro Private Car | 1925-26 |
| Kott | Max | 692 Beaufort Street, Mount Lawley | Oakland | 4665 | Metro Private Car | 1926-27 |
| Kott | Max | 50 Victoria Avenue, Claremont | Oakland | 7933 | Metro Private Car | 1927-28 |
| Kott | Max | 66 Victoria Avenue, Claremont | Chrysler | 670 | Metro Private Car | 1927-28 |
| Kowald | E. P. | Katanning | Chevrolet | KA ● 102 | Katanning Toad Board | 1922-23 |
| Kowald | E. P. | Katanning | Chevrolet | KA ● 102 | Katanning Road Board | 1923-24 |
| Kowald | E. P. | Katanning | Chevrolet | KA ● 102 | Katanning Road Board | 1924-25 |
| Kowald | E. P. | Katanning | Ford | KA ● 144 | Katanning Road Board | 1925-26 |
| Kowald | E. P. | Katanning | Ford | KA ● 144 | Katanning Road Board | 1926-27 |
| Kowald | E. P. | Katanning | Ford | KA ● 144 | Katanning Road Board | 1927-28 |
| Kowald | F. W. | Katanning | Chevrolet | KA ● 102 | Katanning Road Board | 1925-26 |
| Kowald | F. W. | Katanning | Chevrolet | KA ● 102 | Katanning Road Board | 1926-27 |
| Kowald | F. W. | Katanning | Chevrolet | KA ● 102 | Katanning Road Board | 1927-28 |
| Kowald | G. W. R. | Katanning | Ford | KA ● 215 | Katanning Road Board | 1925-26 |
| Kowald | G. W. R. | Katanning | Ford | KA ● 215 | Katanning Road Board | 1926-27 |
| Kowald | G. W. R. | Katanning | Ford | KA ● 215 | Katanning Road Board | 1927-28 |
| Kowald | H. A. | Ewlymartup Broomehill | Ford 19 H. P. | BH ● 14 | Broomehill Road Board | 1922-23 |
| Kowald | H. A. | Ewlymartup, Broomehill | Ford | BH 14 | Broomhill Road Board | 1923 - 1924 |
| Kowald | H. A. | Ewlyamartup Broomehill | Ford | BH ● 14 | Broomehill Road Board | 1924-25 |
| Kowald | H. A. | Katanning | Ford | BH ● 14 | Broomehill Road Board | 1925-26 |
| Kowald | H. A. | Katanning | Ford | BH ● 14 | Broomehill Road Board | 1926-27 |
| Kowald | H. A. | Katanning | Ford | BH ● 14 | Broomehill Road Board | 1927-28 |
| Krakcour | P. | 10 Gill Street, Mount Lawley | Ford | 13031 | Metro Private Car | 1926-27 |
| Krakoner | R. | Kojonup | Ford 20 H.P. | KO 14 | Kojonup Road Board | 1919 |
| Krakouer | P. | 10 Gill Street, Mount Hawthorn | Ford | 13031 | Metro Private Car | 1927-28 |
| Krakouer | R. | Kojonup | Ford 20 H.P. | KO ● 14 | Kojonup Road Board | 1917-18 |
| Krakouer | R. | Kojonup | Buick 6 | KO ● 14 | Kojonup Road Board | 1922-23 |
| Krakouer | R. | Kojonup | Buick | KO ● 14 | Kojonup Road Board | 1923-24 |