I bet if you put a masonry wheel in a 4-1/2" angle grinder, and score the cut on four sides, it will break clean. Angle grinders are as cheap as renting a saw.
I have a masonry saw blade for my 7 1/4 circular saw. Kind of what Dave said, but you get a bit more cut and it's easier to control. A decent diamond blade will last for years and is about $40
Yep, that works good too. I used to have a "scut" Black & Decker circular saw that I used for those things. I had masonry and metal cutting blades. The shaft was a little wobbly, but it did okay. :laughing:
I actually opened a landscaping company last fall and I was prepared to offer full scale lawn service and hardscapers.
-Retaining walls up to 3"
-Patios
-Firepits
-Soil testing
-Tree removal (I don't believe in cutting down big trees unless They were damaged in a storm.)
-many many more....
Unfortunately, I will have to place my business on hold because my primary job requires me to move. Grrrrr! I love working outside like many of you love red meat and fried bacon!