Ah, "faux wood finish" = paint.
Rather than hire an appraiser, the best bet is to have a technician look it over and assess its condition as an instrument. A piano is a musical instrument first and foremost, and the only way to obtain an accurate assessment of its value is to physically ascertain its condition as an instrument, and that can only be done honestly by a qualified technician. If you've had the piano tuned regularly, the tuner ought to be able to give you a pretty fair appraisal of its worth, and he/she probably won't even charge you. If you haven't kept it tuned, tsk, tsk tsk!
If you can give me the brand and serial number, I can tell you what year it was made and perhaps estimate its initial quality. The brand will be cast into the upper right of the cast iron plate under the lid, and the serial number will be a 4-6 digit number stamped into the wood in the vicintiy of the tuning pins, usually toward the right side of the piano. Another factor significantly affecting its value, even as a rebuilding candidate, is if the plate covers the area of the tuning pins, aka the pinblock.
It's also helpful to know the maintenance history of the piano. Has it been regularly tuned? Has it ever been reconditioned/restrung/rebuilt?
If you need to find a qualified tech in your area, this is the national guild, and they have a locator: Piano Technician's Guild
All of that being said, here's some harsh reality in considering selling it, especially since it's been painted: It's sole value is its worth as an instrument, and even if it's a freshly rebuilt piano, it might be worth ~$1,500 tops(as a point of reference, these days it runs ~$3,000 to properly rebuild an upright, and that doesn't include refinishing). If it's in poor condition as an instrument, unless it's an exceptional brand(and even then it doesn't matter much), it won't be worth paying someone to haul it away. Painted-over pianos have a stigma attached to them - it's worse than a weathered, beaten, crackled original finish.
<small>[ 04-17-2006, 08:10 PM: Message edited by: OperaTenor ]</small>