There are people who get an entire regionally-accredited bachelors degree in computer science in a single 6 month semester at Western Governor's University for $4,000. They are rather rare, but it happens.
The university lets you take as many courses as you can pass (serially, one-at-a-time) per semester.
The exams are taken in person, in proctored testing centers such as Prometric or PSI Services where you have to present government ID and you are recorded on video during the exam. So roughly the same threat model as in-person classes where you could hire a smart body double who looked enough like you to attend exams for you at an in-person university.
The university lets you take as many courses as you can pass (serially, one-at-a-time) per semester.