Have you shopped around for used machines or possibly a Chinese machine? Building a machine for hobby use is one thing but if I had a business, I would rather not have to spend my time building, especially if I was a newbie. I just purchased a new Chinese machine last weekend and it was 4'X8' with a 4HP spindle for $6200 ( I paid an extra $600 and picked up the rotary axis also) and it came with a dust collector. You don't need a machine that size so you would probably get it already assembled and running around your budget. I found a US dealer that brings them in and makes sure that they are running right so I didn't have to deal with importing.
If you want to build your own maybe you should look at Finelineautomation Saturn series.