the good news is you dont need much cash to get really strong.
you just need to grill tactical patterns deep into your brain. you need be able to spot tactical potential by knowing the themes well, and have seen them from a variety of angles. you need to be able to caculate deeper and broader.. not to mention cleaner which I think is often overlooked.
you could pay for a sorted tactics book like rienfelds 1001, or try chesstempo or something like that. also tactics trainer here but Im not a fan. (note: the sites are scrambled and not sorted, I think its very important to have them sorted)
openings are irrelevant until you can keep the pieces on the board. any quesitons pm me
So, it's always a good idea to solicit ideas from those who are smarter, better, and more experienced than yourself. In that frame of mind, I'd like to ask the experienced players around the best ways for a relative novice to improve at chess.
Some quick notes: I'm around 1200-1250 strength by my non-expert estimation. Like all players around my rating, I struggle with outright blunders and leaving pieces hanging sometimes. I know common chess ideas like opening principles, normal tactics like forking, double attacks, etc, and basic pawn endgame strategies. I know one opening well as white (Queens Gambit) and I know a few very basic defenses as Black not so well.
So how do I improve? What are the best ways to get better? How can I move past simply knowing basic strategies and a few opening lines and improve my ranking? I have my own ideas but I think it's always best to ask the experts the best way to move forward.
One quick note: I'm a grad student right now, aka dead broke, so any advice that's along the lines of "Pay a GM for private lessons" will just make me cry.