In general, most single-sided PCB work with 0.5mm pitch components can be done by hand with a metal stencil + dry-wall trowel edge, SAC305 Type T4 or T5 paste, hot-air rework hand tool, and or a toaster oven re-flow kit (will often smoke flux due to bad temperature profiles.)
Getting a PCB mostly factory assembled for you is likely the better choice if you live in a building, as dropping hundreds of 100nF MLCC on a project can be brutal.
I guess the answer is yes one can do prototypes by hand if you take design considerations for pad access (sloppy mechanical tolerance for pencil/air rework), but probably one should be spending their time on design for lab EMC/EMI. =3
Robert Feranec does quite a few EE interviews, factory tours, and is generally accurate 97% of the time.