I bought a mini circular saw from Aldi for under £30 and has been great for me. Laid decking, built planters and cut new boards for a shed. I'd recommend for any job where your not needing deep cuts
It really depends on what you want to use it for. Decking, and I'd be inclined to go for a chop saw. Cutting up lengths of wood or board, a track saw is my choice, and the Lidl's one gets another vote from me. If it is a once in a blue moon job, ask friends or family - I'm sure someone will be able to lend you something.
Circular saw from screwfix (cheap one) has done me proud. Not something I use very often but it’s solid!
Buy a track saw not a circular saw. Lidl one is cheap enough
I Bought this Circular Saw for a Decking project, It tackled it with ease. Really pleased with it. (y) https://www.screwfix.com/p/mac-allister-mscs1200-1200w-165mm-electric-circular-saw-220-240v/314gf