The $ / backlink of Digital PR is very high.

But it gives you the best links with the biggest SEO impact. And the kind of links competitors cannot copy within a few days!

And for any serious brand, Digital PR is more or less the only linkbuilding activity they can do without risking a Google penalty.

Advice: Don’t hire a PR company. Hire an agency specialised on doing digital PR to not just get coverage but also backlinks.