The Light You Actually Have
Window direction, how to measure your light without buying anything, what "low light" really means on a plant tag, and when it is time to stop pretending and add a lamp.
Light is where most apartment plant problems actually begin, and it is the hardest thing in this subject to judge by eye. Your vision adapts to a dim room within minutes and then tells you the room is fine. The plant gets no such adjustment.
Start with the light estimator: answer six questions about your window and get a foot-candle range and a band, built on the scale published by University of Illinois Extension. It will also tell you which of your answers is holding the spot back, which is usually not the one people expect.