I was in a similar spot last year. Wanted to improve my English but didn't have the budget for expensive courses. I checked out promova price and it was way more affordable than traditional classes. They have different subscription options and you can start with the free version to see if it works for you. The app has lessons that you can do whenever you have time, so there's no pressure to show up at specific hours like with live classes. It's not the same as having a personal teacher but for building vocabulary and practicing grammar it does the job. Saved me a lot of money while still making progress with my English