All depends how complex you want to get and how much money you want to spend. As a general rule plastic has a limited life. Stainless lasts a long time. I began all grain with a simple gravity system that used two igloo coolers converted to HLT and MLT and a keggle. That cost me about $500. You can do BIAB with a turkey fryer set up and be under $200. There are so many options and so many different vendors it's hard to say one is better than another. Everyone tweaks their system so expect to buy more later. If you are limited on funds I would say stick to extract, make a keggle for a full boil then go for a fermenting chamber so you can control your temperatures.