If one decides to do a basic install system, you only need to do the VFD enclosure, so as a minimum you need an electrical enclosure, VFD, braking resistor, main power disconnect, wiring and some misc. parts which total to around $500. This is outlined in the recommended enclosure build list I have posted. The wiring changes at the lathe control board are outlined in detail in the document provided, basically removing the high voltage wires to the contactors and reconnecting them to the low voltage VFD control inputs. If you are uncomfortable with the electrical get a friend who is and/or an electrician to do the wiring and VFD programming. I figure 2-3 hours of time, if that. Maybe some day QMT will offer a simple VFD package, but I have helped 100's of people with various VFD installs and everyone has been able to do it. That being said, lathes, mills, etc. can be purchased with the VFD installed and/or full blown CNC. The PM-1440BV can be purchased at close to the cost of the 1340GT plus the cost of a basic VFD system. A number of people have gone this route, and have been happy with the lathe. You can also get it with the DRO as part of the package.
www.precisionmatthews.com
I also practiced medicine for 35+ years, and I learned how to do these installs knowing nothing about VFD's. My first VFD build was on my 1340GT took about 3 months to figure out the design, test and figure out the programming. The first 2 months was procrastination as to what to do, there was no information on the web or from QMT at the time. Doing a poor install job and not giving adequate concern for safety and interlock redundancy (what ifs) is a big gripe of mine with individuals that say it won't happen to me. Not understanding what your doing is just as dangerous, whatever the task.
As a hobbyist in the last 12 years I have done quite a few VFD system builds for various machines, but for the 1340GT I only do complete replacement control systems and rarely full system turnkey enclosures. These are primarily designed around the use of a proximity stop control system with 2-3 levels of safety redundancy and all the bells/whistles. Everything electrical is replaced, switch gear, front panel and all the cabling, additional items are spec'd out on the build list. Takes several weeks, cost various by design features and component build list. I do not do this as a business, I make more in 1 hour of medical consulting then one of these systems, so a real PTA. Since shipping has gotten prohibitively expensive turnkey systems are completely individualized primarily for local pickup.