UK Landlord Forum / Life

Hello people,I am new on this blog so I'm not sure if this is way too long.  
I would like to share my story as much to vent my frustration as to get any advice anyone may have. 
I live abroad and have a small flat in London which I have been renting out for several years. During COVID my tenant left and I couldn't come over but the letting agent found a new tenant. A famous pianist. The  flat is fully furnished but she asked to remove some things. I said I couldn't but would give her a considerable discount given the difficult circumstances. She moved in and immediately put nearly all my furniture, pictures and everything into storage without asking permission. I was not pleased. She told the letting agents she would pay for storage. Ok. Difficult times. She  then moved a grand piano in and trouble started with the neighbours. She started playing and running a piano lesson business from the flat. Not allowed. She was a difficult person constantly asking for repairs and handymen when there was no need. After some complaints from neighbours I found out she was subletting on an Airbnb site. I complained to the agents. By this time my letting agents D&G had been bought up by Foxton's. So the property managers had no idea of the background. This didn't help. They went in for an inspection and I saw from the photos that she had redecorated the flat. Changed the wallpaper, curtains, upholstery, blinds. I was furious as the flat was  expensively decorated by an interior designer. All the agency did was  tell her it should all be put back in its original state after the tenancy. 4 months before the tenancy was due to end she sent a letter through her guarantor saying she would not pay any more rent because she had to pay for storage. Plus that we had been discriminating against her by visiting the property. That we were not to claim any deposit etc etc My instinct was to reply and clarify the situation but Foxtons said no they would deal with it.. Next step is that she stops paying rent. They send her reminders. For four months that's all they do. I was sure she was going to leave so there was no point issuing her with eviction notices. Then she went. Leaving 4 months unpaid rent. All my things thankfully back but just piled into the filthy flat with plenty of  damages to walls and fittings. It cost me over 5.000 pounds to get the place back to its original condition. I still have not received anything back from the deposit, the property manager just told me to contact Helpland and during these months believe it or not Foxton's took their commission from the unpaid rent!Why bother with check in/check out reports? Why bother with contracts detailing that all broken lightbulbs must be replaced! Why insist on a guarantor? I don't know whether I should sue the tenant or the agent! But I'm pretty sure that either way I will just incur more costs. And should I trust Helpland?
If you got to the end, thank for reading!

I don't see any basis on which you can sue the agent (maybe ask for the fees back for the service they were failing to supply).
You can sue the tenant for the unpaid rent and the repair costs (allowing for fair wear and tear).

It is not clear when she moved out, or how long since you made a claim on the deposit?  Guarantors are usually a waste of time,  so I assume that they are refusing to cough up. I don' t understand how Foxtons could take their commission from rent arrears? 

My instinct would be to sue her, she sounds really horrible.  She presumably has some money and assets, but of course that does not mean she will pay. It might be nice to get a CCJ against her.  I have a picture in my mind of the bailiffs staggering down flights of stairs with a grand piano!   

TLDR. Agree with JP Keates and heavykarma.

Thanks for your replies. This forum has brought me luck as today Zero Deposit sent a mail saying they have paid the deposit back! To Foxton's of course and I don't see anything on the website, so too soon to celebrate but still it's a step forward.
The tenant left in mid March so it's been nearly four months.

 I'd suggest contacting Helpland with all your documentation and photos to see if they can help with the deposit issue. You might also want to talk to a lawyer about suing the tenant for the unpaid rent and damages, and they can tell you if you have a case against the letting agent too. Also, maybe consider finding a new letting agent since it seems like Foxtons didn't handle things well. Take it step by step and you'll get through this.

Thank-you. I have contacted Helpland and they have sent a LBA. I will definitely never use Foxtons again. I alo wonder if there is some network whereby a tenant like this will set off alarm bells when she tries to find another place. She obviously caused problems to her previous landlord because there were no references and there was a complaint regarding unpaid rent which D&G ignored. Still no sign of the deposit after a week they say it has been paid