I get that this is unsolicited advice, but please take in the spirit it's intended- there is zero judgement from me on this and its the same advice I'd give to a loved one.
If you don't think buying your own property is realistic and you're settled in your area, get your name on the council house and/or housing association lists asap. You might wait years but it's most often a better option for long term renting and generally your home will be your home for as long as you want it to be because you're not at the mercy of a skint landlord or one who decides to sell up to cash in on a property boom or just cannae be arsed anymore.
The ONLY benefit to a private rental is you choose the property you rent rather than receiving an offer of a particular property.
That's why Melvin is prepared to spend the dosh to get his home the way he wants it. He can pretty much guarantee that his flat is home until he decides otherwise. Burst letterboxes notwithstanding, that's also why when his heatings on the blink or he's got a vermin problem or the tiles get blown off the roof etc the problem gets dealt with sooner rather than later. As another tattler said, if the cooncil decided to condemn the building he's in, they will re-home him.
No system is perfect, including being mortgaged btw, but it would be worthwhile exploring your options. There's a lot of brand new social housing being built in my area and I doubt that's unique to the shire, but you need to be on the list to be considered for a tenancy.
We are still living with the Thatcher legacy of selling off really great council properties, without "replacing the stock" unfortunately. i totally get why you would be hesitant to improve your home at your own expense if you feel that would be benefiting your landlord more than you.
Sorry this post got a little bit serious and political