Question about affiliate marketing revenue

Hello guys and girls,

I want to start a journey in affiliate marketing, mostly in SaaS niche and after I grow in this niche, I'd like to start in gambling/casinos niche.
So, my plan is to start 2-3 sites with all kinds of articles and I think the investment would be like 3-4K dollars or more (domains, hosting, themes, plugins, content etc.).
I know it takes time to reach 50-100$ in revenue per day, but from your experience, how much time would it take to reach this revenue?
I know it is about how much time I'll be spending building this, but I want to do it full time.

Thank you!

I am also starting out, and with a very similar strategy, can't wait to hear what others have to say.