I know its probably a bad time to be doing this but I need to make some decisions and treat part of the decking at our new place before I put a bike shelter on it.
I think its been previously stained dark brown, but its pretty rough with lots of grey wood showing through.
I was thinking about a decking cleaner, followed by a good scrub and then painting a light grey or off-white colour. The railings are in better nick so just going to scrub them and paint dark grey/slate. But finding decking paint is pretty rare/expensive.
Any reason not to do this? Why would oil or stain be a better idea, and could we achieve the same light colour?
Any advice appreciated!

Use an oil as it wont flake and look shit within 18 months like most stains can. I can recommend screwfix no nonsense decking oil, cheap as chips, easy to apply and so far looks perfect still even after 3 kids abusing the deck all year.

Scrub with brushes, clean twice with jet wash (deck/patio head), preservative and then 2 coats of oil. Went from this

[url=https://flic.kr/p/viUH4h]IMG_20150628_194621203[/url] by nixie_me, on Flickr

to this

[url=https://flic.kr/p/wERg6u]IMG_20150821_074518582[/url] by nixie_me, on Flickr

I used Barrettine Clear Decking Oil and Barrettine Premier Wood Preservative