Going to have to disagree with a lot of this - see, when I was a kid we had no money. We used a heavy old blue poly tarp and swimming pool mattresses, and crappy cheap bags. You get away with a lot if you only go when you are reasonably assured of good weather, which is not foolproof but worked most of the time for us. And we did get rain - you get that sometimes in the mountains even when forecast is for clear and sunny. You figure it out! Went out in jeans, sweatshirts and whatever we had. You go for two days and you can get away with it. We used the DEET like no one's business, but other than that we did great, slept well, no issues a'tall otherwise my mum wouldn't have budged out the door. Tho when dad hurt his hip when the log rolled on it, she rather insisted we get a travel trailer and stick to tamer stuff.

However, these days it's terribly easy to get cheap synthetics, wool from a thrift store, and rent the pack, bag, pad, tent, and stove. Or to borrow stuff. So that's what I tell people to do until they are reasonably sure they want to keep backpacking, at which point spending the money makes sense.

Misery is never necessary.

But the OP said cheap gear sources, so that's what the OP got from me.
"In the beginner's mind there are many possibilities. In the expert's mind there are few." Shunryu Suzuki