power and phase converter question for soon to arrive mill

Hi Folks, This is my first post to this group. I just recently purchased a used CNC milling machine that has a 4.3hp motor. It should be arriving at my home (Dallas TX area) in about 1.5 to 2 weeks.  So I'm trying to get everything ready for its arrival.  The first task is power. I was thinking of either building  or buying a rotary phase converter panel, and also buying a used 10hp 3 phase 1700-1800 240V motor as the required idler motor. I am currently renting the home I am living in, so I can only do minimal damage to the walls in terms of running cable, etc.  There are two sources of 240 power near to the garage: one is the dryer outlet, and the other is the water heater. The water heater is actually closer to the garage and is therefore a better choice if possible. The seller told me that the machine's manual specifies a 30amp 3 phase 240V power source.  Both the dryer and water heater are on their own 30amp (single phase) circuits. About how much power are a 4.3hp milling machine and appropriate phase converter likely to draw? If my math is correct a 4500watt water heater will draw 18.75 amps; the leftover 11.25 max amps does not seem likely to be enough in my guesstimation. So is the dryer outlet the only option?  If I use the dryer outlet, I'll need @25 ft of wire. What gauge wire should I purchase? I read that you should get a phase converter that is almost twice as big (in terms of HP) as the motor in a CNC mill - hence my search for the

10HP motor.  Do you all know of a good place to get a used 10hp motor (or the whole converter for that matter)  in DFW?  And can anyone paste a link to some good phase converter plans for this machine? I.E. some plans that are not too technically advanced in the required electrical knowledge, but still will yield a great converter at a good price. Thanks a whole lot! Mario