The web interface of the chinese fab houses directly is way better than what these guys offer.
For example JLPCB https://cart.jlcpcb.com/quote?fromDemo=yes
You first order is $10 including parts and assembly for 5 boards with 4 day turn (1 for pcb fab, 3 for assembly). Typically the boards I have done (comparable to complexity to an arduino) are about $20 for 5 copies including fab and assembly. They also have a free cad tool called easyEDA https://easyeda.com/ but I would really recommend kicad. It takes like 5 clicks to go from layout in kicad to boards at jlpcb https://support.jlcpcb.com/article/44-how-to-export-kicad-pc...