Hi Beverley,
You’re right in that shots taken at 72dpi can be made into 300 dpi. But unless the camera has very high resolution, this is not a good practice.
I would focus on the other camera – which is an excellent brand.
I did a quick google search for “best cameras to shoot artwork” and also “best practices to shoot artwork.” There were a ton of suggestions and some good pointers. Lenses and lighting are important.
But once you get your system down, it’s yours!