It’s important to understand that you have a share in the freehold, most likely owned by a company you have set up. Therefore, as a shareholder you cannot simply ignore your Lease, even if it’s a 994 years.
Your Lease is your Agreement with the Freeholder for the long term use of their property. Your tenant has a tenancy Agreement which effectively gives them legal charge of your flat. This doesn’t negate you and them from complying with the Lease.
Your managing agent can and there are cases where they can be held criminally liable with the freeholder for breaches of health and safety and fire risk assessments, so they have every right to remove items stored in communal areas. Though, they ought to inform leaseholders and give them opportunity to remove their items.
A Fire Risk Assessment is required at least every 5 years, with annual documented reviews to show consideration has been given for ongoing risks.
You have to think about a smoke filled communal area and the hazard this will cause to residents and emergency crews as they try to get out and crews coming in with equipment.
I’d take it when you bought your flat, the estate agent would have given you a break down of your floor space. Your solicitor is also likely to have highlighted the area that belongs to you. How would it be fare to other shareholders if some are allowed extra space or take extra space ?
Living in shared property is all about having to be considerate to others and that’s why a Lease exists.
I’m a leaseholder that owns a share of the freehold and has the difficult task of running our building with a managing agent. I hope you can understand the obligations for both sides and will be able to work with your managing agent and your tenant to keeping everyone safe.