Everything you own or are entitled to is an asset.
A $10,000 car with a $5,000 loan against it is a $5,000 asset.
The FMV can be determined by an appraisal or blue book.
For a car, sometimes the best thing to do is to have a dealer tell you what they will pay you for it.
You wrote, "How do I determine the FMV of an asset...?"
A: Vehicles and real property can often be researched online (KBB or the local Assessor website, for example).
Asset valuation of other items may require a professional appraisal.
IF you have legal title or and equitable interest in real estate or personal property, it is an asset regardless of any financial equity, and it must be listed in your bankruptcy.
Valuation? you can look on zillow.com for real estate, Kelly Blue Book or NADA for vehicles, and Craigslist or Ebay for almost anything else. Remember that you, as the owner, probably have a reasonably good idea of the value of your property. Be careful to not overvalue the asset. We tend to do that when it belongs to us. Good Luck!
Be sure to designate "best answer." If you live in Oregon, you may call me for more detailed advice, 503-650-9662. Please be aware that each answer on this website is based upon the facts, or lack thereof, provided in the question. To be sure you get complete and comprehensive answers, based upon the totality of your situation, contact a local attorney who specializes in the area of law that involves your legal problem. Diane L. Gruber has been practicing law in Oregon for 26 years, specializing in family law, bankruptcy, estate planning and probate. Note: Diane L. Gruber does not represent you until a written fee agreement has been signed by you and Diane L. Gruber, and the fee listed in the agreement has been paid.