"well we would like you to do a clean and see how it goes from there!"- Strike 1 for them as far as i'm concerned
For me, the above words from the op and conversation do it for me. It rings alarm bells in my head.
In my experience, people that say the words , "........and we'll see how it goes from there!", tend to be messers. And want cleans on a whim. Which is fine if you price accordingly and don't mind slotting them into your round whenever THEY require it. But, if you have regular customers, albeit, monthly, 8wkly or quarterly, you might not want the faff of irregular work which could screw your busy schedule up.