I had a go at making a crusader pouch out of furniture warehouse leather samples - very pleased with the result as it does the job and can contain the water bottle, aluminium cup and lid, honey stove, meths burner, tinder tin, fire piston, cigarette lighter, tea bags and still have some room to spare - can't quite fit the kitchen sink in (yet) though.
The quality of my leather work is pretty rough but it is good enuf for my purposes - and will be even better when I put a lid on the pouch.
This was my second 'project' the first being a sheath for a laplander - also functional but not of high standard - and I reckon for the cost of the tools/leather working material I have got two useful items for what it would have cost me to buy ready made but still have the kit to make more if I want.