For example, Paranormal Activity had a "production cost" of only "$15,000", and did "$190 million" at the box office. Sounds great, right?

Wrong. First, every low budget production involves calling in a huge number of favors (read: free work) that is not done on normal, funded films. So even the $15K number is ridiculously low if you are trying to compare the issue at stake: money spent on production value.

But let's ignore that. Next up is the cost of prints. A print on a wide release averages about $1200/print. Suppose we order 3000 prints on the Paranormal release. How much did we just spend? $3.6 million. (Without doing a wide release, there's no way to hit $190 million at the box office.)

Wait, that doesn't sound right! The Quora post makes it sound like some heroic filmmaker got their film made for $15K and it "made" $190 million! And now you're telling me they couldn't have even sold tickets without spending another $3.6 million? Yup. The $15K bit is a lie, part of the publicity of the film.

Of course, they don't keep the whole $190 million. Roughly, they'll end up with around 50% of that after the theaters take their cut. So we're really talking $95 million on a $15K production budget, and a $3.6 million print budget.

But wait, there's more: making the correct payments to the production staff, actors, director, etc. and the cost of marketing.

You see, a film that's shot under budget will have to make up those numbers if it does well. There is no free lunch. For our purposes, the amount is likely to increase a $15K budget by 10-100x (not a typo). In many cases, substantially more as top-line talent takes a percentage of that $95 million gross.

And then we hit the advertising. In a nutshell, Hollywood (and in this case, Paramount did the marketing) has a tough time marketing anything in the usual way for under $20 million. So let's go with that, even though I suspect the numbers for Paranormal were higher.

So...with all that, was Paranourmal a hit? Absolutely. Was it an example of a $15K movie that made $190 million. No, not even close: you're a few orders of magnitude off.

The same is true of every other film on that list.

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The real reason Hollywood does not make "low budget" films like the OP seems to want is because even spending zero, nothing, nada on the production budget still incurs $20-30 million in costs to distribute that film.

So ask yourself: if you were going to spend $20-30 million manufacturing and promoting something, wouldn't you want to spend some serious money on the production itself? Wouldn't you want to make sure the story/actors/direction had a high likelihood that people would watch the resulting film?

You would, which brings us to the real problem: actual films cost more.

Suppose you were really frugal, you tailored your story to easy locations, few setups, just a couple of actors, etc. Even then, $200K is pretty low to do a film that would actually be watchable (the "found footage" genere is basically the only kind of film that can be reasonably shot for the under $50K budgets in the Quora article).

So okay, $200K – and you don't have distribution yet, and likely won't get it.

That's a lot of money to "invest" in a film that won't make even it's production costs back. The vast majority of independent filmmakers don't have that kind of money to blow on a film and get zero return. (Raising money there is just as hard as Silicon Valley, if not harder.)

It can be done. Like Crazy is a recent example, made with a $250K production budget and shot on HDSLRs. It's done well enough that the production team will get to have another go on a presumably bigger film.

But it won't be done often, and bitching about the 120 films the Hollywood studios make each year (yes, it really is that low) isn't going to change what they make.