As part of doing my taxes every year I do a calculation as to what my current net worth (assets - debts) is so I know how to set my savings goals for the year. Currently I do not include hard assets such as bullion coins as part of the calculation however, I was recently told that I should along with any other valuable good (e.g. fine art, coins, etc.) that have a know fair market value. Is this in fact true or are there different benefits to using such assets to determine two net worth's (i.e. liquid net and total net worth)?
If the value of these hard assets is significant you probably have them insured, and for significant art work you should have had them appraised as part of getting them insured.
Therefore the process of adding them into the net worth calculation would be trivial.
Your goals should be a mix of liquid assets, and assets that are harder to sell, such as real estate. It should also include those items you are more reluctant to sell.
In some cases these "investments" do need to be included in official calculations, such as applying for a student loan or financial aid, required financial disclosure statements for some government jobs, or applications for government assistance.
"Net worth" is interesting as it can have a different number assigned depending on your intent.
The number I focus on is my total retirement account and any brokerage account. I purposely exclude the value of my house.* This tells me how much I'm able to invest.
My heir would look at it a bit differently. She'd have the cash not only from the house, but from every bit of our possessions that can be sold. For my own purposes, knowing I have a piece of art that might sell for $xxx doesn't mean much, except for insurance purposes.
In your case, if the coins are gold, and held for investment, count them. If they were your grandfather's and you plan to leave them to your own grandkids, I'd leave them out.
* I make this point for two reasons - as someone with an eye toward retirement, the house doesn't get included in the 4% return math that I apply to the retirement and stock accounts. Also, in our situation, even when we downsize at retirement, the move isn't likely to pull much cash out of the house, it will be a lateral move. For those who plan to move from a McMansion in the suburbs of NY or Boston to a modest home in a lower cost of living elsewhere, that difference may be very important, and should be taken into account. This is simply how we handle this.