The flamethrower can do damage over a large area. Any vehicles or pedestrians will be instantly set on fire within range. Most pedestrians usually die when lit on fire and only the healthiest car will survive the fire. Fire can be put out by the fire hose on a Firetruck or, in GTA San Andreas, with a Fire Extinguisher. Special vehicles that are fireproofed will be immune from damage from the flamethrower. It is one of the two only weapons that can destroy a Rhino.
The flames from the flamethrower will only damage vehicles and pedestrians. In GTA San Andreas only, the flames can be created on the ground and can spread, making the fire extremely hard to put out if one is started with the flamethrower, even if only one little flame was made to start out with. The flames on the ground will not affect pedestrians but can affect vehicles and the player. If a pedestrian catches on fire, the pedestrian will usually run wildly until his or her death.
If you activate the flame thrower in front of a mirror, the fire will not show up on it.
Harwood, Portland Island - On roof of the Head Radio building. It will be on a block-like object. This object is too high for the character to jump on, so you must plan accordingly in order to get there. A Hidden Package will be nearby.There is a Video here
Starfish Island - In the swimming pool of the Rockstar House northwest of the Mansion.
Viceport, Vice City Mainland - By the building near the road in the southwest part of Viceport, south of the Viceport Pay 'n' Spray. From the Viceport Pay 'n' Spray, head south along the road. As you near the road curve going east, you should see the weapon icon to your right.