So 100k for 2-4 years?
Now that's gonna make me rich!

That's why I tell people writing scripts to not think of them a 'golden lottery tickets'. You get $5K to tide you over until your windfall,
hopefully, in a couple years. Still, $5K is more than squat ($ 0).
I've exaggerated a bit about 1m to 100k
But, yes, as a new writer I have more chances to get a producer with 100k budget than producers with 1m++. And I can't be like "I want my script at the hands of Nolan or Spielberg, no less!".
As a new writer, you're focused on selling a script. A producer OR director might pick it up. And if you have an agent, you can sometimes be surprised who reads the script (whether they choose to make it, is a separate question). Sometimes an actor or actress falls for a script and leads production through his/her connections (as Keitel did for Tarantino). So being involved in other productions can be an asset to connect with directors and actors!
Moreover, I think movie like my "Rappatron Device", which is actually called "VoXDrop"

can be shot on 1-2M and be good. I mean... most of the needed actors are 20-25 years old. Well... maybe I'll need 50-100 people to create a "crowd", but I don't need real actors for that. There are no Sci-Fi locations, history decorations, choreography, costumes or high quality visual effects. And the scene INT locations repeat themselves many times. What I don't really know, is how much the cost distribution, marketing and HR.
"That's on a need to know basis, and you don't need to know"

It's not so much age as union status. There are so many distribution outlets and that impacts the marketing. Typically producers look at a 20/80 production budget--20% above line (talent-actors/directors/writer), 80% below line (crew, locations, effects, etc.). Some distribution (film, DVD, streaming, festivals) in the domestic (us) and/or international markets require marketing and labeling. There is another forum dedicated entirely to this topic. You might go there and ask this question.
As a rough estimate, the marketing & distribution budget can be up to half the production budget. Again these are rough figures for the sake of discussion.
A 90 page script will usually take about 8 weeks to shoot professionally (5 day weeks for 12 hrs for about 38 shoot days).
For an actor, the rate can range from $100/day to $843/day or more in some cases.
We're looking at $3800 per lead actor (assuming an Ultra Low SAG agreement)
For a Hollywood production, those SAG acting rates and directing rates will be significantly higher.
So for a basic story, we have 4 leads and 6 supporting- 4 * 3800 + 6 * 2850 = $ 32,300 (for actors)
Director, DP, ADs add another $10 K roughly.
Add in meals, crew and directing expenses as well as paperwork, PAs, locations, music, props, post-production, etc., it's easy to see why a quality independent film nowadays can have heavy budgets. Because of inflation, Tarantino's $30K initial budget (hey, 16 mm film?) would have to be almost $ 75K today.
Consider a decent range independent film (Sundance quality) that uses Reds and Avid editing suite and SAG/non-union actors.
$ 750K film = $250K (marketing & distribution, rights, some post-production expenses) + $400K (crew, locations, FX, permits, food, lodging, travel, PAs, Extras) + $100K (actors, directors, writer/s, composer)
So a 2% cut for the writer = $ 15K, though you'd be paid $10K = $15K - $5K (option)
Not huge, but I'm not going to turn my nose up at $10 K two years down the road.
I mention this because screenwriters think it's only about their story and producers will pay them hundreds or millions on sight. I want to be a voice of reason. Movies take time to make. The bigger the production, the more time and money, big money. When you're a producer and looking at budgets over $500K, you want a
great script that can attract actors, directors and
investors who want a return AND be ready to go into production quickly.
Production companies often have parameters for scripts that interest them because they already have actors/locations/assets in mind they can use inexpensively. While your script may be innovative, from the numbers perspective, "doing what's made money in the past" makes sense. You tap an existing viewing market. That's why there's so many imitation movies and re-makes. Love 'em, hate 'em people go to see 'em. If a producer loves your story, they'll option it. They'll have me read it and make recommendations for cleaning it up. Usually they ask the original writer to re-work it. They then work to interest directors and actors in being involved. With that package (script, director, actor) they then go looking for money.
Getting people to invest in a movie is difficult because they are prone to fail. Given the choice of buying Microsoft stock compared to NewbieNerd stock, the conservative investor will go with Microsoft despite the potential gain. The same is true of investors in movies. Name talent draws in the bucks. "You got DeNiro on board, sure I'm in." "Soderberg's directing? Alright, I'll invest."
A director may see your story and decide he likes it but can "re-write it to be better". An actor may see a part as awesome but want the role to showcase his/her talents. The producer will often let them. Their credits are what get the movie financed. At least until you have some credits of your own. Script consultants work in the background to "clean up" the script based on production notes. At some point, you need to choose between money and/or credit.
Truth is, outside of the screenwriter (via option) and those who get paid during production (mostly crew, many actors are on deferment in small projects), most don't see a dime if the project doesn't break even. Unless you are working in Hollywood, New York, or Chicago in the film/television industry, you will likely not be making a consistent, living wage as a screenwriter. I don't mean that as a discouragement but as a reality check. It has nothing to do with your writing but access to being actively involved in the industry. Many great writer/directors got their start writing copy in the advertising industry (Cameron for one). Working behind the scenes as a script consultant and/or reader is another way. While you don't often get credit, you get experience, some pay, and connections.
Smaller indies still look at budgets of $50-100 K for professional quality shoots that use rental Reds, permits, crew, etc. You can find non-union actors who will work on deferment, especially around college towns. In these cases, a writer may get $1000 for an option and deferment for a small percentage after distribution. Sometimes, just getting credit and seeing your script made into a movie is worth the effort.
Even if not Spielberg, if a produced/established director wished to option one of my scripts, I wouldn't say no because I was offered less than standard. Less money is sometimes a worthwhile swap, though I would require getting screen credit and points. Most indie directors and producers are okay with that.
Again, don't expect one script will make you instantly rich. To start seeing instant money, pick up a camera. They always need camera operators.
Good luck.