I work as a consultant and collect AFTER the transaction was successful. I am filing 2013, now, on an extension. The work and expense was started and performed mostly in 2013 yet wasn't paid until 2014. I wish to report the income on the 2013 return and pay what I owe asap. Is this ok to do and will it cause any conflict when the client submits their 1099 end of 2014? (it was for far more than $600). Thank you.