CNC Jr Kit, can it be done cheaper?

Hi,

New to the group and also new to the CNC world. I'm looking into
getting a CNC machine and was wondering if anyone has experience with
the CNC Jr machine at www.cncmasters.com? The machine itself looks
like the grizzly machine that one can buy for around $2000. On the
cncmasters website, they sell a cnc conversion kit for around $4000.
Does anyone know of a similar kit that would be cheaper? Or, any
sites that would give some guidance so I could do it myself?

I've also considered the smaller mills like the Taig or Sherline but
I'm worried that I will outgrow those machines too quickly.

Thanks for any ideas,

Craig