I never outsource... It's not for me. I've only outsourced for content writers because I'm not an English-speaking writer, and I've never had any luck with it.
So back in the day i used scraped content from various tools from wicked article creator to kontemt machine, then spimmers and now AI which is perfect.
Why don't you automate your SEO? I don't accept niche-relevant backlinks. You don't need backlinks from niche-relevant sites; instead, you want content-relevant backlinks. Who said tiered link building isn't working anymore? It's working better than ever before. Just try it yourself instead of making statements here. All my sites are built on scraped content, now using AI, and I build links with various SEO tools like GSA SER, Ranker X, etc. It works well, and Google now gives even more instant positive reactions to it, thanks to Google's speedy indexing.
Most fail because they use duplicate content for each backlink, and they never care about brandable anchor texts. I don't think buying links from someone is a good idea. Why not automate it yourself? It only takes a few days to automate, and it's almost set and forget.
Most strategies work if you know what you're doing. You can do 100 percent competition analysis instead of trying to check SERPs and deciding if the niche is suitable for your strategy. You've been making the same mistake for years and now asking the best provider to do it, even though it's a big mistake .
My opinion is to grab all the resources and try it yourself. Most failures are due to outsourcing. If anyone knows how to do SEO, why would they sell it to someone else when they can earn more than that?
I own a site which I built with scraped content, and it's purely garbage, but the link building profile is clean and looks slick (no silly so-called niche edits and PBNs), just contextual tiered link building using various tools, but a very clean drip-feeding campaign, and it's still in the top 10, and with the latest updates, it's even improved.
In conclusion, never ever outsource. Just do it yourself.