They seek work providing landlords with insurance (8,7)
I believe the answer is:
covering letters
'they seek work' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.
'providing landlords with insurance' is the wordplay.
'providing' becomes 'ing' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'landlords' becomes 'letters' (people who let property).
'with' is a charade indicator (letters next to each other).
'insurance' becomes 'cover' (I've seen this before).
'ing'+'letters'='ingletters'
'ingletters' put after 'cover' is 'COVERING LETTERS'.
Can you help me to learn more?
(Another definition for covering letters that I've seen is " documentation to accompany goods maybe".)