Thanks for your reply.
It's quite simple really, the document governs the extent of your liability. There are no statutory safeguards to protect you. Ultimately it's a matter for negotiation and it will depend on how flexible the agent/landlord is.
The most important things to look for are the term. It will refer to the tenancy agreement's term and will probably state that you are liable for costs arising during the term but also including any holding over or extension. This means that if they remain in the property past the fixed term either on a statutory periodic tenancy or if they agree to an extension (regardless of the term) then you will be liable for costs arising from their further period of occupation.
You should seek to limit the length of your liability to only the length of the initial term and delete the words relating to holding over or extensions. State that you shall consider being a guarantor to any extension but require site of the proposed tenancy agreement to confirm you are happy with extending the term. Try to reason with them that there is a difference in guaranteeing a 6 month tenancy and a 2 year extension and that it is fair that you should know what you are getting yourself in for, with this amendment securing that.
It will also state that you are liable for all costs. You can attempt to seek to limit your liability to merely just the rent payable under the tenancy agreement rather than all costs. If they do not accept this then you should seek to limit you liability to a sum of money, so to the rents plus a further sum that you can negotiate to take account of other potential costs.
I would also ask for a clause to be included obligating the agent/landlord to inform you immediately of any missed rental payments or damage to the property.
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