What tool/strategy you use to quickly estimate repair cost?

[Michael Ndjondo makadi]

To all flippers, wholesalers, fixer-upper in particular and investors in general. As I finally started my RE investment journey (BRRRR), I quickly stumbled upon to this very issue: how to quickly estimate repair cost without using a contractor and gage an ARV. I watched multiple videos, listened to several podcasts but for my first deal I had to rely on a couple of contractors to provide some repair estimate. This process was not free as I excepted but it was time consuming to schedule appointments. So my question is primarily to know which tool/strategy you use and how accurate do you think that method is? As for the ARV, I used redfin as it provides some nice features to help one select down properties based upon similarity, size, location, and many other options. However, this process is more of art than a precise technique. Hence, I wanted also to know what tool/strategy do you use to estimate ARV.