Active ingredients questions

Hi all,

Trying to decide between Hims and Ro.

Hims offers 2-in-1 with Fin/Min. And 4-in-1 with Fin/Min/Ketoconazole/Biotin

--- Ketoconazole being an anti-fungal but shows promise in the anagen phase. Nice writeup in the beginners guide.

Ro offers 3-in-1 with Fin/Min/Tretinoin.

--- Tretinoin being an acne treatment and also shows promise in the anagen phase.

Question 1 - Is there a reason to use anything beyond just Fin/Min?

Question 2 - If you use a product with Ketoconazole (anti-fungal), does that limit any other anti-fungal usage in the future?

Question 3 - If you use a product with Biotin, does that "add" to the biotin you would get from a daily vitamin supplement?