If my father gifts me the house at its full value tomorrow, how much would he be taxed?

The annual gift maximum is the amount that does not use up any of the lifetime gift tax exemption. If he still has his entire unified gift and estate tax exemption amount available, he can gift the house to you and simply file a gift tax return using up a portion of his exemption, and pay no tax. My concern with lifetime gifts is with capital gains on a subsequent sale by you. If you inherit the property you receive a free step-up in basis as of your father's death, as though you paid full fair value for it. If you turn around and sell it for that value, say $600K, you realize no gains on the sale so you pay no federal income taxes. (As for state taxes, that varies state to state). If instead of inheriting the property you receive it as a lifetime gift, your basis in the property is the same as your father's; no step up. If your dad bought it for 100K, that's your basis, and when you turn around to sell it you pay income taxes on the gains: 600K minus 100K = 500K gains ("income"). The federal taxes will probably be about 35%, or $175,000.00.

Your father would make the gift of the house to you by gift deed. The value of the gift is its net fair market value. The first $14,000.00 is a freebie (annual exclusion) so that is also deducted. The balance is the amount that must be reported on a gift tax return (form 709). However, unless your father has already used his lifetime exemption (currently $5 million 450k) with prior gifts, no gift tax would be paid. It would merely reduce what is left of his life time exemption at his death. The bigger question is why the gift is being considered. Under current law if your father dies and you inherit the property, you will receive a 'step up' in basis. The recipient of a gift get a 'carry over' of basis. That could be a significant capital gain tax issue.

The $14,000 would be tax free of estate tax. The rest would be subject to estate tax if his estate exceeds the maximum value of exemption ($2.4 M now). For capital gains you would take his basis, not current value so you're likely to have a significant tax hit there.