I have only seen one voltage drop problem in a residence & it was a double wide that had to have near 150 feet of 14-2 to the furthest outlet. When one of those 12 amp vacuum cleaners was plugged into it, it about choked, voltage fell to 85-90 volts.

The homeowner had hired me to find code violations so he could sue the home builder.I found a few, but couldn't help him with the voltage drop problem.

Few things are harder to put up with than the annoyance of a good example.