Many plant species can grow under artificial light only. I care for many low light plants in office environments where the plants receive only overhead standard fluorescent lighting 9-5, 5 days per week and they do fine. Other types of light will support species that require more intense light.
Because cost is a concern, I suggest you use LED's because they are far more energy efficient. You will need the lights on a minimum of 8 hours per day. I also suggest that you figure out your lighting first, then get a decent light meter to determine what light intensity you have in various locations. Then, select your plants based on the available light and the light required for various species that interest you. Light is the key factor.
Humidity is a much lesser concern. If you have many plants in a relatively small enclosed space, then the plants and soil will generate sufficient humidity levels for all but a few fern and bog species.
