If you date Helena Wankstein, you can find one in front of her house in Flint Range, Flint County (since the Bandito has no doors, you can take it anytime after starting to date her). It can also be found on a beach west of the city hall in San Fierro. You can import it from Easter Basin on Tuesdays for $12,000, after bringing 5 cars from the second Export list.
There are multiple locations where you can find the BF Injection parked, such as Santa Maria Beach in Los Santos. You can find another one on the beach south of Mount Chiliad, as well as on the south part of the beach west of San Fierro. If you finish "Dirt Track" at Blackfield Stadium, one will spawn right outside the stadium. There's also one at the Snake Farm outside of Verdant Meadows in Las Venturas.
You can find a Caddy parked in front of the Avispa Country Club in San Fierro, as well as driving around it. You can also find it driving around the Yellow Bell Golf Course in Prickle Pine, Las Venturas. There is also a Caddy at the movie studio in Vinewood, Los Santos.