Normalize overuse of "precondition" endpoints in Collection and its folders & environments - collections

Question

I have been using Postman so much and built a lot of useful things in it, but now need to implement one more thing.
Briefly:
Need to create test cases to test a correct records counting for every institution.
Now I handled it like that
Structure:
---------Collection
-------Folder
---Districts(folder)
-some folders with tests
---Colleges(folder)
-some folders with tests
---Schools(folder)
-Principal(Folder with test in Schools folder)
where these requests:
POST: Create a list
where in Tests:
var jList = JSON.parse(responseBody);
postman.setEnvironmentVariable("list_id", jList.data.id);
POST: Add some filters to list
GET: lists/{{list_id}} whete in "Test" code:
```
var allLists = JSON.parse(responseBody);
pm.test("test count", function () {
const value = allLists.data.count;
pm.expect(typeof value === 'number').to.eql(true);
pm.expect(value > 0 && value < 999999).to.eql(true);
}); // I check if the number(made in step№2 in a range we need
```
DELETE: delete this list
I guess I do 'overhead work' adding POST(create a list) and -DELETE endpoints in every folder, can I somehow bring it out to environment or variable and execute it before every POST: Add some filters to list and -DELETE endpoint after that
Something like general BeforeEach and AfterEach
Perhaps can I even bring this(below) out in one place for every separate test?
pm.test("test count", function () {
const value = allLists.data.count;
pm.expect(typeof value === 'number').to.eql(true);
pm.expect(value > 0 && value < 999999).to.eql(true);
});
Here is an example how it looks like if it not difficult, give me a piece of advice! Thanks