So this returning client of mine just finished renovating one of his houses and needed a post construction clean. I quoted just under $400 for the whole thing (4 bed 3 bath, 2 storey house). He complains about the price and asks for a no invoice discount so I tell him $350.
As I get there with my crew he mentions the windows need cleaning as well, which wasn't included in the quote so I just do them for free to avoid further headaches from this dude.
He told me the house would be empty of tradies and machinery to ensure we could do it 100% but as we get there this guy is still painting and there was equipment everywhere.
The three bathrooms looked like they were done by a 5 year old and there was grouting EVERYWHERE, which took forever to clean off, having to revisit the bathrooms several times we finally got 2 of them right with the exception of the one downstairs which I overlooked before leaving.
Dude sends me an email asking for a $50 refund because "none of the bathrooms were up to standard" (unfortunately I did not take a photo and he only sent me photos of the one downstairs which was obviously overlooked). It was either that or I send a team back there for more headaches. I chose to refund him $33 which is our hourly rate and tell him to not contract us for any future work; he comes back and says it is not negotiable and if I do not refund the $17 (miserable prick) he will "make this a bigger headache for me".
Is this a legal threat? What grounds does he have over non invoiced work and a $17 refund? Do I just refund him the $17 and tell him Merry Xmas?