What do i do if tenant won't leave at end of lease?

There’s no point in FT leases now for landlords unless it’s less than six months and even then, tenants can cause problems by over holding. Letting a house is treated like other rental contracts that just roll over, eg things like utilities, broadband, mobiles, bins, health insurance, crèche places etc. Those suppliers don’t pull the service as long as the user keeps paying the bill or cancels by giving notice. The difference with letting property long term is that the supplier can’t stop or remove the supply even when the user stops paying for the rental.

Letting is also similar to hiring for a job that becomes indefinite after a six month probation period. After that, employers need a good reason to fire someone. But, an employer can restrict access to their business premises if there is a dispute/suspension but a landlord can’t restrict access. An employer can have a FT contract for x years but a landlord can’t. Employment law is complex and very few companies now would hire someone without taking legal advice and then going through rigorous hiring procedures. Mistakes cost.

Rental law is skewed in favour of tenants IMO and landlords need to get smart and pay for legal advice before handing over a very expensive asset to another person whether it’s a stranger, friend, relative, foreigner, or local.

Solicitors are not law teachers. They won't go through legislation . If you have a specific problem they will provide advice for a fee. In a lot of cases they will obtain advice from counsel. There may be some lawyer/tutors who would be prepared to go through legislation for a fee.