Morty's IVs

Hello there fellow trainers!
I've always been a perfectionist and tried to get the best stats on my mortys.
But one question arised while looking at the formulas in this page:
How do IVs work?
I assumed they worked just like in Pokemon (a random interger between 0 and 16), but it either isn't like that or I'm very unlucky and have never found a morty with good rolls.
Also, does "basic" Morty get the same IVs everytime?
I've tried restarting a couple times, and he always had the same stats.

I have one advice for you if you want your Mortys to have the best stats (I'm glad I'm not the only one), don't give em level up mega seeds. It'll lower their bonus stat on HP. So if you want a Tanky Morty with High HP, don't give them Level up mega seeds. Level them up regularly. If you add Level up mega seed, you'll receive stat bonus Hp but it will be reduced. So it's better to level them up regularly.

I'm just curious but will it affect the hp stat if you train using the bootcamp or if you combine two mortys that level up seeds have been used on and you combine it will it affect the stat

Idk about the bootcamp, (I'm afraid to try it out myself, but I will get into it in the future) but I have figured out that if you start with a low level Morty, he'll be stronger. Example: The Mortys that you receive in the tournaments. About the combination, I advice that you pick your team early on because if you combine Mortys that you recently captured and are High leveled ones, they're not going to receive bonus that much, that's why it is advisable to use a low level Morty (start from the bottom going up). Say no to Wild High level Mortys. It's better if you level them up regularly and it applies to combination as well. If you combine a Buff Morty that is level 5 or something and another Level 5, you'll get a level 12 or 10 Wrestler Morty and level that combination from now on. It's going to be stronger than a wild Wrestler Morty with the same Level as you. You'll notice it in the Hp. Hope this clears your question.

On combining, I'd like to advise that you should combine Basic Mortys until they achieve their final Combination. They'll be a lot stronger if you combine them starting from their basic form.

That happens thanks to EVs, each time your morty wins a fight against other mortys, yours gets a percentage of their stats (up to a cap), so if you level them up without fighting you may not reach the cap before lvl 100 and end up with lower stats, including HP. That's why using Levelup Seeds or Bootcamp is not recommended.

As said before, what I want to know is: What are the possible IV rolls in this game? 0 to 10? -5 to 20?
Because according to my own data, it is not 0 to 16, like in Pokemon