Problem:
John Smith, as the owner of an apartment building, receives and makes the following payments during 2008.
Received in Jan 2008 rent that was due in Dec 2007.... $5,000
Received in Dec 2008 rent not due until Jan 2009.... $4,000
Security deposit which is to be refunded when tenant vacates the apartment... $500
How much rental income must John Smith include on his 2008 income tax return?