...i believe there is a mechanism where an arbiter is appointed to deal with these kind of commercial lease ....
Hello,
While I think that may be a fairly standard clause in most leases, I'm not sure it's actually a legal requirement. Also, lets not forget that there is no lease in existence here.
If it were me, I would approach the tenant and explain to them that they are not paying anywhere near market rent and you as the owner are entitled to receive market rent.
I would tell them that you were going to bring in a recognised professional 3rd party to inspect the property and make a recommendation on what the current market rent should be. You'd like to agree a suitable time to have the professional enter the property to survey it, take measurements etc. so as to cause least disruption to your tenant and you'll give them a copy of the documented findings of the professional, to support your claim for a rent increase.
Invite them to do the exact same thing, with a recognised professional of their choosing (and that they will be paying for), so both professionals findings can be compared and used as grounds for rent negotiation.
If they won't agree to the above, then I would tell them that regretfully, you will have no choice but to write to them through your solicitor offering a long term lease at what you consider to be fair market rent and if they don't agree to and sign a lease within a reasonable time frame, you will have no other choice but to seek to evict them. I would tell them that this is the last thing that you want to do, that you've appreciated them being good tenants for the last number of years etc. but that they need to be fair here.
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