Easiest way to connect C64 to modern computer screen?

So, I recently got this C64 for free, and I've been wanting to test it. However, figuring out how to connect a monitor has led me to various forums with home-made adapters that require soldering, a 5-pin DIN to 4xRCA to...? My monitor has VGA and HDMI, etc, the usual modern inputs. Someone claimed that the voltages are different which will lead to artifacts and to put a resistor somewhere. I found some box thing from China that looks promising but it's around 150 usd.

What would you recommend for this? Is the expensive box my best bet?

I have no TV or anything that can input RF, just a computer monitor.