I have been think a lot on this subject also and I think that I agree with what pros is saying.
On my 2 builds that I have going on right now, my first one while I haven't gone the super cheap route (gotoh tuners, Hipshot bridge, Seymour Duncan pickups, making my own cavity covers, string blocks and odd and ends) I was able to keep the whole total after wood around $500 but on my second build the guy I'm doing it for wanted to spare no expense, expensive wood, prs pickups ($160 a piece wtf?!?), schaller tuners I'm already in the $1000-1100 range. There's no way I could do this on my own dime so I will be buying cheap parts for the future for builds and just upgrading after the guitar is finished, then those parts can be passed onto the next build.