Recommendations for beginner mistakes on a tight budget [v1]

I want to write something more comprehensive about this later but starting with a quick post to gather thoughts. Spent the last few weekends digging into this and the deeper I go the more questions I have. Long-time lurker, first-time poster.

I want to write something more comprehensive about this later but starting with a quick post to gather thoughts. Been thinking about this for a while and curious what the community thinks. This came up at a meetup recently and the room was split, so curious what the broader community thinks.