re: Cutting straight lines with a circular saw

I have an old kobalt sliding miter saw with a 7 1/4" blade that I got for like 99 bucks 10 years ago. Before I really got I to woodworking to do small tasks around the house. Stores on a shelf if needed. Even now that I have a garage full of heavy duty tools, I've still not upgraded that saw. I don't use my miter saw for "furniture grade" accurate cuts. It just chops down boards to round about length with good enough square-ness. Which for framing and such is more than fine. For super accurate cuts, I use a table saw and sled. I may upgrade to a really good miter saw when I have too much money in my pocket, but until then this saw would have to die on me. And I have a problem buying expensive tools and still don't care to have an expensive miter saw.