I agree with Dan. I use an all in one HP with dual trays in my Ford Explorer, but my sister, who drives a car and doesnt have spare room in the back seat, has the HP 404n. We also have an Epson scanner which is pure magic. I will carry that into people’s homes when I need to scan documents.
Brother printers take too much energy to run. Because the HPs are energy efficient, they only use 600 watts. What that means is that it runs at 1200 watts peak (while printing). That means if you purchase a sine wave inverter at 1500 (cannot be a regular inverter, which is cheaper), you will comfortably be able to run your printer in your car. The best inverters come with a remote although I just set my inverter under the passenger seat and turn it on manually as needed.
This setup earns me more money as I can take closings I previously couldnt because I can print on the go. I went to a radio installation shop and they installed it directly to the battery. You can then place your printer on your back seat or if there is room, on the floorboard of the backseat, like my sister does.
I dont recommend you print in peoples’ homes just because it is cumbersome and takes time. My goal is in and out in 30 minutes although, of course, it depends on each customer. Printing as you are driving down the street…makes money because it saves time.
Good luck to you!