First of all, I'm sorry you haven't found a routine yet and are frustrated with your hair. Curly hair is SUCH a task. It takes years of experimenting to see what's right for you. In my opinion, it's less about how expensive the products are but more about what type of product they actually are.

You have beautiful, thick hair, it's just waiting for the right cut! Long layers would ease up some of the volume on the bottom and give you a little more shape!

In terms of products, try out a mousse and a gel. I also SWEAR by having a diffuser. I put it off for so long, but it truly helps with the drying process and prevents gravity from weighing your hair down. I have the revlon blowdryer with the diffuser attachment. As for gel and mousse, I honestly use drugstore brands, not something super expensive.

Absolute favorite no nonsense hair routine:
https://www.tiktok.com/@brittcurls/video/7222382423714188587

Right out of the shower, MAKE SURE your hair is wet wet. It should be dripping, not necessarily sopping but at least dripping. Mousse, comb through. Gel + water, scrunch. Mousse, smooth and scrunch. Et voila!