If you had a good violin that resonated properly, you would get yet another interesting component to tuning. You can feel the resonance and tension, and you start to develop this strange sense of "knowing" the string is tuned as it should be just from that inaudible little vibration that happens when your fingers gloss over the strings. It only works on your own violin, though, because the resonance of each violin is different.

Honestly, I think it's probably a good idea for you that you don't have a teacher. You read here, and then you freely admit that you didn't follow any of the advise of the people you claim to be knowledgeable. Clearly, following the advise of another person is not in your personality, so if you were taking lessons, you might be doing your own thing regardless of your teacher's advise. That would honestly make lessons a waste of time and money, not to mention absolutely miserable for your teacher.

You won't get far without a good teacher and a good instrument though. Your violin doesn't do what a violin should do, and it is just a matter of time before you experience all of the numerous issues that cheap violins have. You might be able to throw away $70, but by my definition, that doesn't make you poor. I can't throw away $70, or $5 for that matter. Perhaps I am a bit jaded, but I have seen way too many wannabe violinists throw away money on a cheap instrument and quit a few months later. If you are going to give up in a few months, that is all the more reason that you should rent. It costs about $20 a month, and you get a $500 instrument that works properly instead of a $70 instrument that doesn't.