When it comes to some of the older manual typewriters, condition is king and a big determinant of price. For the budget range you're in, you're more likely to get something in mediocre shape that's going to require some work: cleaning, repairs, parts, other.
Your best bet is to go to a repair shop that sells machines, put your hands on them, try them out, ask lots of questions, then buy your favorite. Your time is worth money and productivity, so buy something you like out of the gate and you'll save a lot in the long run. You'll probably be happier and better off in the long run with something in the £200-400 range. It will also give you something you can start using right away to get your work done rather than faffing about.
Try shops from this list: https://site.xavier.edu/polt/typewriters/tw-repair.html
I'd generally endorse most of the advice on models you'll find in these sources which are geared specifically toward writers, all three sources have lots experience and reasonable bona fides to make such recommendations. (Though they do tend toward some of the more expensive portables rather than the sturdier and more economical standard machines.)
https://www.youtube.com/watch?v=h9dXflhDed0<br />
https://www.youtube.com/watch?v=aKMt-aCHZZk<br />
https://typewriterreview.com/2020/01/10/top-10-writerly-typewriters/
Beyond this Just My Typewriter has a few short videos that'll give you a crash course on Typewriter 101: https://www.youtube.com/playlist?list=PLJtHauPh529XYHI5QNj5w9PUdi89pOXsS
u/jbhusker's advice is solid if you prefer that sort of machine instead.
reply to u/ArcherNF at https://old.reddit.com/r/typewriters/comments/1hdgte4/looking_for_a_recommendation/
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