There were times when people overlooked the blemish in the door because they had done it themselves. For me, the question never even arose; I am simply not willing to pay 50 EUR/net labor cost for the floor layer who ultimately does nothing other than click the laminate or engineered parquet into place. Sure, back then one could have borrowed 50,000 EUR more. But the money has to be paid back, as you already said...
But now we are in a thread where people are complaining about soaring construction costs and craftsmen who put fantasy prices in their offers. This is of course also because many builders go into debt up to their eyeballs just to never have to touch a shovel. The craftsmen naturally take advantage of this "need," who can blame them.
Craftsmen have often looked at me quite puzzled when I said, "I am the paver..." or "Yes, I’m doing the interior finishing including doors myself..." or "No, we’re taking the oven from our old kitchen..." or (my personal favorite from yesterday) "for 500 EUR I would have had that (furniture for the living room) assembled..."