If you decide to sell your property with vacant possession, you can issue a notice of eviction. This could be a Section 8 notice if they’ve broken their tenancy agreement or a Section 21 notice. You can also issue both at the same time (if appropriate).
Both types of notice have benefits and drawbacks, so you should consider which is the most suitable for your circumstances. For example, you’ll need to give at least two months’ notice for a Section 21 order, but in general, this is more straightforward as you won’t usually need to go to court to enforce it (so long as all your paperwork is filed correctly).
In contrast, a Section 8 order means you’ll only need to give two weeks’ notice, but the tenant can contest this, and you may end up going to court.