Hi Paul,
With the advent of digital photography, there is no doubt real estate
photographs look a lot spiffier these days than in decades past.
I suspect many use HDR.
For example see
https://fstoppers.com/strobe-light/h...otography-3135
If you haven't tried it, you need a tripod and you can start with a program like Photomatix.
See
http://www.hdrsoft.com/
It's probably not surprising they would reach for something fast to do like HDR rather than try and
spend hours fiddling with fixed lighting as if they were photographing for Vanity Fair. Time is money
and the real estate business is hot at the moment.
The digital commercial real estate photography has got to the point here
that some of them ask if you want digital furniture inserted as an extra.
I smile when I see the obligatory big screen TV that always happens to
be showing a view of the Sydney Opera House on it.
And they love some shots with all the lights on so it looks warm.
There is always that twilight exterior shot with all the lights glowing warming inside
and HDR makes that easy.
Good luck with your sale.