I'm looking for a cheap frame to use as a commuter, I have all the kit to put on it. Needs to be road/gravel based, take discs and also be able to fit a 6'5" gimp like me. Cheapest I've found so far is the Sondor Camino at £250 but concerned it will be a bit small for me. Happy to go secod hand if anyone has any bargains.
Try Evans clearance frame, they had a few pinnacles when I was looking
Ahem
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F112836300151
PX Kaffenback? £175 at the moment, it's a fairly un-glamorous commuter type frame, not the most inspiring to ride but ticks the boxes you have and easily fits my 6'4" body.
Frame or bike?
Go Outdoors has the Kona Rove AL on at £500-10%, and I have son doing DofE so another 10% off....
+1 for Evans. Arkose frames from £230 and they include a headset.
I have a large frame from one of these I could let you have for £50 + shipping.
If it interests you, I'll dig it out and send photos when I get home.