Deductions & credits

Thank you.  I see lots of responses stating that FMV on date-of-death is to be used to determine cost basis when one goes to sell the inherited property, but....

1) How do we determine FMV?  

2) Do we need to engage a formal assessor or real estate agent to obtain an FMV?  Is that good enough?

3) What's the true book-of-record the IRS will refer to when determining if there was a captain gain or not?

 

Thank you, Ed