Lighting, Light Fixtures, Ceiling and Exhaust Fans - SOS - mystery wires...

OK - am attemtpting to tap power off of an existing outlet to powere a new switch and light. The weird thing is that the wires from this box come from a separate breaker box on the exterior of the house (which also controls the heatpump). To make matter worse... the wires are not marked on the end that had been run into the outlet and there is no tape to identify them. I have four wires, three red and one black... on the breaker box end two of the three red wires are marked with tape (one green, one white) but I can't tell which ones these correspond to on the box end (some 20 ft away) by tugging. My questions:

1) Does the presence of 4 wires indicate that this might have been rigged as a 220?
2) Is there a way to identify which wire is which?
3) Should I just give up and call an electrician? lol

Thanks!

It indicates to me that amatuer who didn't know or didn't care about code has been working on your system.
You are not allowed to remark any color wire to white or green below #6 guage.

That was or first assumption aswe didn't even really know that this box wasn't just a normal box until opening it up. The house seems to have had a hot tub once upon a time clos eto this area so perhaps it was the plug for that? Believe that the house was built by one of three brothers (they were all neighbors) who were general contractors who clearly bent the rules and code to suit themselves. Thanks for the reply.