Deductions & credits

1. If the grantor has died and the home is being sold by the trust after their death (and the trust has become irrevocable at this point), does Section 121 exemption still apply?
2. If Section 121 exemption does apply, does that prevent the preparer from claiming a capital loss if the sales price is less than basis?
3. If the price is discounted by 25% off of FMV by a sale to the surviving significant other (not a spouse, not a beneficiary of the trust, and not a community property state), does this prevent taking a capital loss if answer to 2 above is "no"? 4. Does the trust use FMV on date of death for basis?