They sent me 5 databases and asked me to analyse them to figure out how website traffic affects sales. They added a bunch of criteria + code submission + email summary for non-technical stakeholders + README. In the email invite, they said they only expect it to take 3-5 hours (???). I wanted to get it right, so spent days on it, analysing all the fields, documenting them correctly and modelling it. Then they took 3 weeks to send us an answer. I actually contacted them asking about my application and that's when they remembered to respond to us. They were 100% just looking for free labour and put this advert up to get people to come do their work for them.