Realistic conditions for fuel container explosion First off, I'm not actually trying to blow anything up. Also, my apologies if this isn't the right SE to ask. If so, I'd appreciate it if you could point me to the right SE.
I'm writing something where at a point I need a big explosion to happen. I've done some digging and I found out that the old bullet-fired-at-gas-tank trope is essentially just a trope, and that it alone is unlikely to cause an explosion.
The explosion needs to happen near a big mansion on an otherwise uninhabited island. The mansion is powered by an outdoor generator that runs on some kind of fuel, for example propane, though it can be anything else that makes sense and can more easily get me the explosion I need. There are fuel containers
to refill the generator sitting somewhere outside the mansion, and they need to be accidentally blown up during an action sequence.
The ideal explosion would be strong enough to blow up the closest wall of the mansion, so that the fire can spread inside the mansion, and this leads to my first issue: I have no idea if it's realistic to expect such a dramatic effect or not—for all I know, it might take far more fuel than it makes sense to keep in stock.
Secondly, as said just shooting one of the containers won't trigger an explosion. I understand that you need the right mixture of oxygen and fuel, and the containers would have to be exposed to sufficient heat for some time before they actually blow up. I thought that, maybe, if some containers are shot and start leaking, and then the leaked fuel somehow catches fire during the sequence, this might trigger an explosion, because air would start leaking into the containers that got a hole punched in them.
To sum up, my questions are:

Can a fuel explosion realistically blow up a nearby wall and spread a cloud of fire into the mansion so that at least the nearest room is almost completely on fire very quickly, without unrealistically huge amounts of fuel involved?

Can the explosion be caused by a bunch of fuel cans that were hit by bullets, started leaking, and were heated up by the flames that followed when the leaked fuel somehow caught fire? Would this take too long to happen (eg, ten minutes), or could it happen within a minute or two?
The topic of explosives in movie production is a specialty application as one does not generally employ classic explosives!
In movies, the aim is NOT to kill/injure anyone (especially, your famous lead actor). As such, one can select even a flameless explosive, which, for example, could include Ammonium nitrite ($\ce{NH4NO2}$). The latter is primarily a pressure explosive which, per a chain reaction, quickly releases a massive amount of gas. Such explosives find applications, for example, in blasting in coal mines. Apparently, mines can develop a potentially explosive mixture of methane and air, where a flame/spark could result in a massive secondary explosion!
Also, distinct from a battlefield setting, consider low brisance explosives, which do not produce lethal shockwaves.
In essence, your objective should differ significantly from the design/use of military-grade explosives. Instead, aim at much flash and dust, but less lethal. The sound level of the explosion can be addressed in the post-editing of the film.
To accomplish this, you need more research and the opinion of someone who actually specializes in this area.