Ask HN: Where is the best place to find an account manager for our SaaS product?

We're a B2B SaaS startup that has recently done a funding round. We are looking to hire a Senior Account Manager role for our business based in the US (Ideally west coast).

Are there any good startup based job boards? We aren't a YC company so can't list on here.

We have been through a recruiter and paid around $20k for a candidate who didn't work out after 3 months. We have a warranty period and they are now looking for a replacement, but I don't necessarily feel that they are coming up with great candidates.

General job boards seem to attract stacks of candidates who haven't actually read the job requirements.

Any ideas would be greatly appreciated.