Thank you for sending me this Ask ^^, I’m sorry for only answering it now.
I’ve occasionally recommended ‘Betterdry’ because they are very cheap (usually just 1€ per diaper), while they are super thick and comfortable. But this is a typical European-market diaper and it’s more expensive elsewhere.
Cheap incontinence diapers that I like are: tena ultima slip, seguna comfort slip maxi, forma care x-plus, molicare maxi slip, drylife super. You could check which ones of these are sold wherever you live and which one is cheap.
ABDL diapers are always gonna be more expensive than incontinence diapers. The €3 per diaper that you mentioned is indeed quite expensive for a thing that you’re going to throw away after a few hours of use. Maybe you can see it like a drink at a café? Though usually you buy a full package of it plus shipping, which makes it quite a big initial purchase and therefore it’s more difficult to see it as individual smaller purchases. I like all diapers from Bambino (especially Bambino Cloudee), I really like the Rearz Princess Pink, and I like the Littleforbig “baby cuties”, which I still need to post the pictures of to my tumblr blog. I’ll put a teaser picture of that at the bottom of this message ^^
It’s fun to have a few packages of cheap diapers for whenever you want to wear a diaper for a few hours and a few packages of more expensive diapers for when you want to feel that extra bit special ^^. Don’t feel bad for not wearing ABDL diapers, though. If you have fun in incontinence diapers then no one will tell you that you shouldn’t have that fun, right? Some people wear a cheap diaper and an ABDL diaper on top of that so they can “reuse” the ABDL diaper a few times before wearing it for real. I’ve never worn 2 diapers at the same time, though, so I don’t know how that feels.
I primarily choose diapers that look good on me and that look good on pictures. Like I’ve often worn diapers from “crinklz” cus they look cute on photos and people seem to enjoy them, but I probably wouldn’t wear one if I wasn’t taking pictures of myself cus they have a weird fit around my thighs. It’s unfortunate that it’s a little bit of trial and error to see which diaper fits you well. The bambino cloudee and the Rearz Princess Pink fit me really well and I really enjoy wearing those. They make me feel super little and I can fully get into the adult baby mindset when I wear one of those.
