system
Given the following post, respond as if you're commenting on Reddit:
human
Am I being fleeced?

Morning all, non-developer here with a quick question. I am having an app built and have just been quoted 16 hours for a button on a webpage that will launch the app (Android or IOS). I have (very) basic knowledge of HTML and do web design myself and 16 hours seems like a lot. However, I am also aware that people often grossly underestimate the work that goes into things outside their own realm of expertise, so am a bit unsure of what to think. Thoughts?
gpt
"The Button" doesn't exist on its own.  
One might need to adjust multiple things on that page to make it fit it. You might also want to pass some data from that page into the app, and that's additional complexity (and thus, work).  
Add things like tests for that data transfer - and it can easily become 16+ hour job.