Do you want to become a pilot or are you after a salary?
What's your age?
CTC "white tail" is risky in that there's no real assurance of a job at the end. You might be lucky or you may not be. Who knows? Are you comfortable servicing that debt load to your parents? Are they comfortable potentially waiting 15+ years for their money back?
Before diving into the buy to let market, have a look at some of the new proposals that are being kicked around by the Chancellor.
As for the do we have the right to refuse to operate there. Sort of. You can refuse but you'd better have a very good reason - especially if the operator has put in alternate measures for security. Keep refusing? You'll probably need to find another job.