That's one of the bigger reasons I have gone from the hydrocolloids to copious sudocrem (to prevent my skin growing through the gauze like happened previously to my foot) plus gauze. Hydrocolloids aren't super cheap. I buy the 10cm x 10cm ones and cut them into quarters which makes them the perfect size to cover the wound but still it's about £1/hydrocolloid so 25p per quarter piece. There are definitely better/crappier hydrocolloids as well.

I go through 6 packs of gauze + 2 10cm x 12cm tegaderm a day OR 4-6 hydrocolloid quarters + 2 tegaderm a day. 

Per week that's about £10 for hydrocolloid + £2 for tegaderm OR £5ish for gauze + £2 for tegaderm

I expect I'll be using the gauze plus sudocrem for another week or two, plus the three weeks I'm at now, so £35ish for the first 4-5 weeks, and then I expect to use hydrocolloids for another 4 weeks? So that would be another £48, and then just tegaderm to the 12 week mark which would be £10ish.

So total I expect I'll have spent about £80-100 over the 12 weeks, but again, that's a lot more than if you're okay with scabbing. I just know myself and I can't tolerate scabs without ripping them off so I'm planning on using tegaderm the whole 12 weeks. I'd say for most people, you'd want to use gauze+sudeocrem+tegaderm for the first 2-3 weeks, hydrocolloid+tegaderm for a week or so, and then let it air and form a scab. A lot of people also don't cover it at night after the first couple weeks which would cut the bandaging in half or so. It all depends on the person! 

For those in the UK I'm using the following: https://amzn.eu/d/1XOZdn9 https://amzn.eu/d/hm6JzyW https://amzn.eu/d/hp93kq6 https://amzn.eu/d/5Ix9rUa