thank you. The officer you have spoken with is not wholly wrong in what she has told you but also is not wholly right. The position would be that as things stand, you would be reliant upon the landlord to take action in relation to the fence. If you decide to proceed with the purchase, then as the new owner, you could seek to take action yourself to recover the land but there is no guarantee from what you say, that that action would be successful if the neighbour or the landlord sought to resist the application you made.
After 10 years, providing the adjoining neighbour or landlord can demonstrate that the land has been physically and practically enclosed within their garden and occupied by the landlord or in practice it would be the tenant for a period of 10 years or more in the incorrect but honest belief that the land comprised part of their garden, then this can be grounds for claiming what is known as adverse possession-this is also sometimes colloquially referred to as squatters rights. If they cannot show that the occupation of the land was in the honest belief that it belonged to the neighbouring property, the application for adverse possession would fail and you would be entitled to recover the land in question but without knowing what position they may take and what evidence they may have to support it, it is difficult to second-guess the outcome of any such adverse possession defence they may raise or indeed even if they would raise one.
If you become the owner of the property, you can seek to reposition the fence to the line you believe represents your boundary. If they refuse, you would need to consider self help whereby you simply relocate the fence in ensuring that the damages caused to it or seeking an injunction to require that the fence is moved.
The advantage of self-help is that it is quick and relatively cheap to accomplish but has the risk that the landlord may make an application for adverse possession in respect of the land which if successful, would mean the fence would have to be put back. It also has a risk that if the fence does not belong to you, that the landlord could claim criminal damage if it is damaged in the process.
The advantage of applying for an injunction using the following form is that it would give a degree of legal certainty as regards ***** ***** but will incur court fees: