You don’t have a lifetime interest. What you have is a licence/tenancy at will although you would probably be entitled to a lease for a fixed period. It depends whether you want the argument in court and whether they want to let you have a lease or not.
They could give you notice to quit and you could defend it on the basis that you had exclusive possession and therefore you have a lease. The leading case is Street v Mountford.
However, you may not want the argument because the rent which would apply would be the market rent which is probably going to be more than £25 per year.
The fact that you may have been renting for so long, does not give you any right to buy the property. If the seller is willing to sell that you are willing to buy, the seller is able to ask for any price it likes which can be low, high, or extortionate.
Assuming that you would be buying at the market price, it depends on whether it’s worthwhile paying whatever that price is compared to the next 10 years for example which is going to cost you £250 also bearing in mind that they could increase the rent to whatever the market rent is..
Can I clarify else anything for you?
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