It can be difficult for expats to find Romanian courses. There are plenty of good teachers out there, but few structured courses that go beyond the A1 level.
I tried three that I can recommend.
Online evening course (a1, a2)
Punto Iberica runs modules on nouns, verbs, and conversation classes in the evenings. These can be quite exhausting at the end of a long day, so we wouldn’t recommend them if you are also studying another language (like German or Hungarian). However, there is relevant homework.
Some of the material they use can be accessed for free, but the teacher knows how to use it and adds a lot of value by giving constant feedback.
If you sign up for a degree at a Romanian university, you can also take the first year learning Romanian.
Intensive online course (A1, A2, B1, B2)
Rolang School runs two-week intensive courses that race through the grammar pretty quickly. You can take these at levels A1, A2, B1, and B2. It is exhausting, but worth it for the super motivated. At the end of the course, I could understand everything I read in the newspaper.
There are exams at the end and certificates. It is not as fun and social as a summer school, but the other students and teacher are good to work with.
The book is good for the course but not necessarily intended for self-study. They also have a verb book that I haven’t tried yet.
Summer school (A1, A2, B1/B2 conversational levels)
The UBB runs a three-week course on language and culture. There is not only the opportunity to learn the language but also to see Cluj and the surrounding area while making new friends (and perhaps future business contacts.)
You might even meet the author of the book in one of your classes. (I am not a fan of the health advice in the book, but the teaching is great and they usually offer at least three levels.) I only know of one student who used the books for self-study, and he thought it was good. I am not so sure; there are elements that are interesting on their own, but it did help to have a teacher guide us through the materials.
Although I already had the grammar and vocabulary to deal with any situation and read books and newspapers before starting this course, it still added to my understanding of grammar and vocabulary and general fluency.
While they did not have a final exam, one student did take an optional exam at the end and achieved C1 level.
I have also heard people say positive things about the Rolang School summer course. And Punto Iberica also seems to run a great summer school.