Agency worker and mortgages

Manchee

My partner and I are on the road to buying our own place, I currently work as a permanent employee where as my partner works for an agency. He has been in his current job for just over a year (no luck with being made perm by the company he works at rather than staying as agency staff, it was the plan originally but you know what they say about the best laid plans..!), we are going to be seeing a broker face to face to discuss our situation but thought others on here may have experienced a similar situation.

Worst comes to worst we can look at buying in just my name for the time being (with a view to adding him on after fixed period ends and we look at changing mortgage, assuming his situation has changed by then) as my wage would be enough assuming a 4.5x lend to yearly wage but obviously it would be better for us both to be on the mortgage application (more protection for him, higher joint earnings which would hopefully make for a smoother application rather than being right on the threshold of the max lend amount etc).

Whats the general view with one applicant being agency employed? Anyone know?