Make sure you factor in the cost of travel to collect the newspapers and leaflets if the agent doesn't drop them off at your home.
I applied in my local-ish area but it's rural with strung out villages so wouldn't have been cost-effective for me. The start of the nearest round to me is about 4.5 miles away. As I was on their database though I was asked to stand in for a couple of issues when the regular deliverer was on holiday. I enjoyed doing it but distances involved between groups of houses and the loooong driveways at each house meant it was really hard work and I reckon I barely covered my petrol costs

. If I lived somewhere like you obviously do and with a round like you mention I definitely would do it though. Don't hang about too long deciding if you want to do it, these sort of jobs get snapped up pretty quickly.
Local free newspapers aren't delivered in my immediate villages, too far out, and the agent dropped them off at my home as a favour when I stood in. He wanted to talk to me anyway to make sure I was fully au fait with what to do with the leaflets etc

. Plus, being paid in cash he had to come round and pay me. Definitely not cost-effective for him as it was several miles out of his way. He said he would definitely employ me again if the rounds I was doing came up permanently but I'd have to make arrangements to go somewhere to pick up the papers each week. He wasn't too keen though especially with the payment situation as it was cash-only and he needed to hand it over personally.