Here is an example of what you can reach with one light and a little bit of sense. There are two portraits of one of my pals in Burgos. The shots was taken with a speedlight flash and a silver umbrella. Is a inexpensive set very affordable and quick. A black backdrop was used for background, holded with two clamps.
Studio shots of music band "DVICIO". Lighted with Elinchrom 3000 generator and 2 Elinchrom 3000A heads, using 1x1m softboxes.