Out the car window is about right. Back in film days when I had a film lab, one of my customers was a woman who shot for one of the freebie listing publications.
She went from house to house, usually only exteriors, 1 or 2 shots, on slide film. She had to pay for her own film and processing, gas for her car, her area was about 100 miles north to south and maybe 30 miles east to west, on a good day maybe 25 houses for $5.00 each.
When the company decided to go digital, they lowered the amount payed to $3.00 since she didn't need to buy film anymore.....
She became a waitress, made more in tips in one day than driving around shooting houses.