The own brand we use there is about 2p per nappy difference between using the pull ups and the taped nappies, so not a significant difference. The pull ups have Peppa Pig on them so he doesn't fight having them on so much
Thinking some more, he does 12-14 hours in his night nappy without leaking, which is a bamboo fitted, wool cover and hemp booster. If I could figure out an affordable way to make wool work, in the day time that would probably make a huge difference, but if we use what we have with secured flats or prefolds the nappy always ends up falling down even though the wool stays where it is. Trying different wool covers is expensive and we only have 3 fitteds now. I'd need atleast 12 to use full time, not accounting for drying time and at that point it's probably cheaper to use the pulls ups until he trains.
Fitteds wouldn't fix the poop issue though, but I guess it's a little easier to scrub out?