He is very kind and generous normally,
How long have you been with him OP?
Because this switch from "generous" to "self-interested tightwad" is highly suspicious.
You will lose £480 in tax credits, he proposes £200 'contribution' ... so this guy actually reckons YOU should pay £280 a month for the privilege of housing HIM?
I'm in shared ownership at the moment so Don expect him to pay any costs towards the rent, I own my share.
Why? It costs YOU money to pay for that roof.
It would cost HIM money to pay for his own roof.
Why do you feel that you somehow ought not to ask him to pay half the cost of a shared roof?
Yes I do want him to move in but this is niggling at me
So it should.
When did he move out of the property he has just sold? (Or has he not moved out yet?)
Where is he living now?
Nobody falls in love as fast as a man who wants a roof over his head & a built-in housekeeper. Sorry OP that won't be what you want to hear ... but am sure you've seen enough cocklodger threads around here to remain very, very wary.
If you said NO to his request to move in, what would his plan be?
Does he even have a back-up plan?
Or is he expecting you to just go along with his (frankly, very cheeky) request to house him?
I cannot believe you are considering paying £280 a month to have this man live with you. Or that your question is "is the amount of money fair" instead of "why is this man taking the piss out of me?"
I think you should say NO for now.
Just to see how he responds. I think it will be very revealing. Because I think he HAS no back-up plan, & he is taking you for granted.