Mars Hydro light with a mean well power driver should be a good budget set up. Youll need an inline duct fan with temperature and humidity control (I recommend the Ac infinity cloudiness pro) and carbon filter to keep smell down. You can get a cheap amazon tent that you can squeeze in a closet. Other things like fabric pots, ph up and down, ph/tds tester, coco coir soil etc. My friend was putting 5 gallon buckets outside and catching rainwater and using that to water his plant, absolutely do not use tap. PH is critical, test it going in and test the run off
When it comes to seeds I've heard mephisto had the best genetics for autoflowers. I learned all this stuff like 5-6 years ago so the game may have evolved since then. The cool thing about growing your own stuff is if you find a strain you like you can just grow massive amounts of it. My friend had so much left over after his first grow he was able to sell the surplus and cover a good chunk of the initial cost of everything