This question suggested the verb consumere to represent time spent/taken. I wonder what would be the appropriate way to ask "how long does something take?". For some reason "quot/quotus/quam tempus hic consumit?" feels wrong for me. (Please tell me, if it fine to use them.)
One option to avoid the 'problem' is simply by asking "when something is going to happen?" — is that the only way to handle this in Latin? Or you would suggest another way to phrase that question?