Selling an estate or letting agency can generate a significant capital gain — and the rate you pay depends on decisions made before a buyer appears. This guide covers CGT basics and current rates, the difference between asset and share sale tax treatment (asset sale from a limited company can attract an effective 50-55% rate vs 18% on a qualifying share sale), BADR qualifying conditions for agency owners, earn-out taxation under Marren v Ingles (CGT arises at completion before earn-out cash is received), non-compete payment rules, vendor loan notes, and the self-assessment payment deadline. Tax advice before heads of terms — not after — is the single most important planning point.