Former President in small house, gone (6)
I believe the answer is:
hoover
'former president' is the definition.
'hoover' can be an answer for 'president' (I've seen this before). I'm unsure of the 'former' bit.
'small house gone' is the wordplay.
'small house' becomes 'ho' (abbreviation for house; 'small' asks for a short form).
'gone' becomes 'over' (I can't justify this - if you can you should give a lot more credence to this answer).
'ho'+'over'='HOOVER'
'in' is the link.
Can you help me to learn more?
(Other definitions for hoover that I've seen before include "J Edgar . . . . . . was FBI chief" , "J Edgar ...... was FBI boss." , "Type of 5 down" , "US president in House throughout" , "Vacuum-cleaner" .)