How to Estimate ARV and Rehab Costs?

[Christian Sabatini]

While looking for potential investments, I've tended to steer away from analyzing deals that require heavy rehab simply because I am not sure how to estimate rehab costs. I've watched the BiggerPockets video going over how to estimate ARV (based on comps of your post-rehab property, etc.), but how do I know how much I actually would need to put into a property?

Any feedback is greatly appreciated!