For Real Estate photography I use my own professional grade Canon equipment, and am a current member of Canon Professional Services (CPS).
The actual equipment used varies from job to job, but may include (all personally owned):
Canon 5DIII - full frame DSLR camera
Canon EF 17-40mm 1:4 L USM lens
Canon EF 24-105mm 1:4 L IS USM lens
Canon EF 24-70mm 1:2.8 L USM lens
Additional equipment includes:
Tripods, pole for pole/aerial photography, external lighting (flashes and remotes), etc
On1 Photo RAW
I'm a firm believer that it is the photographer who creates the image, and not the equipment. However the correct equipment can enable or impede the ability to achieve a particular look. Through many years of experience I've come to rely on the above equipment to produce the results I am after.