Not required. Bill of sale to buyer is necessary. It's your plate you can keep it. You can transfer it provided tag is valid.
IRS would prolly say yes. Also yes about keeping the plate. Just the sticker needs renewed. Actually neither of those is a priority for Federal Agencies.I went in to get new sticker..worried because I was about to have it end turned out.. I was off by a year. Had to pay two years. Apparently no rush....wouldn't recommend that behavior.
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