Every year I get an average of 3 to 4 offers from companies in China, mostly located in Shenzhen, who offer me to make PCBs for my amps.
They make 2-layer as well as 4-layer PCBs, offer from the purchase of 20 pcs. to design the layout of the PCB according to my schematics free of charge and also offer to equip the PCBs with components and solder them in a soldering bath.
When selecting components, you have the opportunity of choosing between different quality levels.
However, I can't say anything about the prices because I was never interested in their offers due to my conviction.
If that were the case, I might have done it that way a long time ago.
But it makes a significant difference and with a PCB based amp you will never achieve the sound quality, the three-dimensionality of the tone, the liveliness and dynamics or the playing feel that you achieve with a PTP design.