Here:

Probably not, if it starts in the toaster oven it are still a threat, but likely not an economically sound threat. I probably have the advantage in that regard, I have a fore extinguisher and a smoke detector so I'm better prepared. It'll also never start in the fire extinguisher, it'll have to bring its own.

If it's just in there burning Richard Ramirez style, then it doesn’t matter who has more fire extinguishers, it is time to roll them dice. Frankly it’s always a dice roll, I’ve seen a literal parishioner with an extinguisher take out a fairly big fire with a 30ft (estimate) squirt because the fire wasn’t too big yet, (nor was the fire as good of a shot and hadn’t learned his extinguisher properly, thankfully). What you carry matters less than getting shots on significant parts of your fire quickly, you want to hit first and hit an area that is important, regardless of fire, you could beat a fire with a class d or with a class b, if the fire is an appropriate type. Of course, that said, you have a higher liklihood of one of those squirts hitting a significant target the bigger the hose is and the squirt channels will be different, and depending on armor which the fire in the toaster oven likely has none of you may need the squirty bois to punch through it, but I’d take my chances.

The real issue is he has the initiative, that’d present the most problems. Of course, he’s get put out sometime. I suppose the real question becomes how did I discover the fire was there? Did I see it? Hear the fire alarm banging around? Were the flames as such that I’d go fight it myself or would I potentially involve fire department? All that makes a difference in the scenario. If I walk into my kitchen and there's just a fire up there who has the drop on me that bad, but if I go up and he has a contact weapon like a fire or fire, I have the distance advantage with the extinguisher. If I hear it up there and know it is a big fire somehow not just like a mouse, the firemen are just getting called, I’ll outsource. If I hear him and think it may be a small fire and I go to investigate, we’re back to “does he have the drop on me or do I have the distance advantage.”

Still, in any case, the fire will be easier to deal with than the fire. Less time, less money, and maybe he has a fire but maybe not and maybe it doesn’t matter if he does.

How's that, sport?