Best and worst experiences working with freelance dev talent?

This question is for anyone that has hired contractors for software projects. What was your best and worst experience?

I've been speaking with founders in this community who've shared their stories with:

The good - Devs that deliver great quality product and help on repeat projects over time.

The bad & ugly - Horror stories of software builds going months and tens of thousands of dollars over budget.

Most of what I've been hearing tends towards the latter, so I'm interested in hearing more perspectives. For transparency, I'm building a no-code agency for early stage marketplaces and want to deliver the best experience possible. Insights here will certainly be helpful to me as well as, I hope, other founders (especially non-technical) looking to bring on freelance talent!