It can be cheaper still if you find an old computer with a parallel port and use a parallel port breakout board instead of the ethernet break out board and/or use the drivers off of a arduino cnc shield instead of the tb6600’s that I used. @dkj4linux has a write up on that here: Inexpensive LinuxCNC interface for MPCNC
That said I like the mesa card enough that I’ll probably be buying them again for future projects.