I think the point is that for 50 GBP you will get a much higher quality typesetting than spending 1 GBP on the API.
As.usual, it depends on the use case. If you are producing a textbook or something that requires high quality typesetting, you will probably pay for it.
If not, you can use a tool like this one but you will have to accept certain margin of error.
I will let you do it for me. I usually work late at night just before the deadline. What’s your phone number?