Thanks for your reply.
If it is a standard lease then it will have a forfeiture clause, most probably based on the time scale I confirmed to you. If the rent has been outstanding for the period of time stated then you have the right to forfeit the lease (ie. Terminate it) and take back possession of the property at that point.
You would also be able to sue landlord for the loss you have suffered, so the unpaid rent, the rent remaining on the lease (though you will likely only get judgement on the amount of rent you would have earned until such time as you could reasonably have been expected to re-let the premises), legal fees and any other direct loss you have suffered as a result of the breach of non-payment of rent or other breaches of the tenant's covenant (including the disrepair caused by them).
If you are empowered by the lease to take back possession of the property then you need not apply for a Court order but you should speak to your solicitor. They will advise that notice is served on the tenant pursuant to the forfeiture clause in the lease. Things can get sticky if you attempt to take possession (ie. Potential allegations etc). Once notice has been served you can instruct a bailiff to take possession, though there is nothing preventing you doing it yourself though this is not advisable for the reason I just mentioned.
If you have a rent deposit then you will be able to make deduction in respect of the loss above provided it is standard form.
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