Construction lights are mostly heaters. Most films (everything
except extended-red stuff like SFX200 and aerial surveillance
films) don't respond well to light that red, they're a fire risk
(especially near diffusion material for softening) and they're
unbearable for portrait subjects in warm climates.  If you want
to start out cheap, get a big old manual hotshoe flash. You'll
still find it useful as a secondary light later on when you buy
a proper monolight, e.g. for use as a hair light, background
spot or fill.