I would say an essential bangernomics key point is fixing stuff yourself. If you take a car to the garage to fit a water pump or brakes or ignition stuff its pointless. As is buying brand new parts to fit (unless its economic to do so) – buying used parts is a key.
I would say another key is buying a car based solely on condition. Obviously dont buy an MX5 if you need to carry people and bikes around, but otherwise consider anything. Look out for cars which people don’t want anymore. All cars have seats for people and a boot so buying an uncool car reaps dividends.
My Volvo 940 cost £400. Yes really! It had £10k spent on it in the previous 5 years before I bought it. It’s flippin massive (I’m not kidding, I got a 3 seater sofa INSIDE it one day), has a reputation for comfort and reliability and its easy to work on and parts are cheap. Fully galvanised and no rust. I’ve spent some cash on it as its a car I’ve always wanted (lowered suspension, bigger wheels etc) but in relaity I spent only about £100 getting it through its MOT once I’d had it for 8 months so its good for another year. It had a full stainless exhaust on it before I bought it and 4 Michelin Cross Climate tyres too (which cost £400 on their own!)
It’s also now quite fast. 😉 And RWD. 😆
It was cheap because its stuck between the classic Volvo models and the new ones so prices are rock bottom (but climbing).