If you blew 150k on materials, you should have a high enough craft to pick a HQ synth to profit from. Check out your GC supply/provision requests for an idea. Just don't flood the market and you should have enough for repairs. This sounds less like an inability to make gil, and more like an inability to hold on to it. Farm your own items, at 50 it should be fairly easy. Be conservative with your teleports and strategically place your favored locations.