Good Day: Well a 300 AMP service. Cool. What everyone is thinking about is this 100KW has a 66 gallon fuel tank. At full load this is good for 8 hours of operation. You will not be using quite so much, but you have to plan for this fuel usage. You may get up to 10 hours on a full tank. AUX Fuel usage is capable of refilling the tank automatically from an external source. So the gen goes from about 1/4 tank to about 3/4 tank when in operation. A 60KW would do for you better, but you have what you have. When finished, this puppy will be a gem.
Next, the gen set delivers 347AMPs per phase. The data plate indicates this shown on page 0006 00-25 with change 2 in TM 9-6115-729-10 and it is often thought of as total current, but this is false. A 10KW set to 120VAC provides 104 AMPS. You got 10 times this. Your house and shop will probably load it to about 35-40% at best. The neighbor will add another 10%. You may get up to 50% load if you use everything on it. I do not believe this will occur and you will probably load it to about 40% total. If you believe this is enough for your uses, supercool. Once it is all in order, you will find that cat engine will just purr. It may slobber after a bit, but there are ways to mitigate this issue. I'll do a scratchy head trick on that monitoring circuitry, and look into the DVR programming and see what can be done. We usually were very happy if it ran as the Tech Manuals say it should in the war zones. Special Ops used a lot of them. Follow the books, and get-r-right, then I'll see about that 120/240 thing. One issue I wonder about is; how far away is your neighbor? There is what is called line loss on distribution systems. This may play a bit with the voltage setting where one end is a bit high and the other end a little low if the neighbor is a bit distant. Ask your electrician about the change over circuits so you can get an idea about those costs. Then the costs to run a line to the neighbor. The electrician can also provide an idea about line loss. If you are up on all that type stuff, I recommend a stubby pencil trick for a bit. Let us know what your progress is.