Update: it was the immigration police that came . I paid the THB 2000 in cash with no receipt given. It was very apparent not to question and for an easy visa process, we had to get 3 independent neighbours to verify I’ve been living here, I just paid and they went away happy with all paperwork signed and photos taken .
I’m reading all the replies. You have all answered my question in as much as you have heard of the fee! We have spoken to the immigration office and it’s confirmed they have passed over this home visit to local police to do the check.
I guess I will pay to avoid any future issues with visas. My wife being Thai says I should just pay and not question the police. Thanks for your help everyone, it’s not worth me making a big thing about this although I will ask for a receipt for my records