Mr Shifta - don't get the "if it's not yours it's not insured" bit. Sounds like a typical loss adjuster trying to screw the customer. When I was trading I made sure my policy covered customers cars, tools, the lot. In fact one day I recall looking around the workshop (my previous, much larger, one) and thought jeez, better up the contents value; one of my customers had three Astons in there, two DB2's and a DB4GT Le Mans and sometimes his BMW as well, of which only two or three were created by their competitions dept.
Fortunately I had very few fires, and those were tiny. Always preferred CO2 extinguishers - seen too many foam ones fail despite proper servicing and was never overly impressed with dry powder (remember to turn those upside down and shake vigorously at least once a year, else the powder will form a 'cake' in the bottom).
added - thing I found with foam extinguishers was their unreliability in actually going off. And then, if they did, the mess 'cause you can't stop them. CO2 for me!
