How do you build your Go-To-Market strategy?

I found few interesting solutions i’m using, but it depends on what the needs are. These are all for outbound as a replacement for marketing: - Apollo (www.apollo.io) with huge db of emails, but its quite expensive - Warm Leads (www.WarmLeads.io), service that sends fresh leads every month from companies that raised millions and are looking to outsource - with only one time payment - the best value-money I found - Instantly (www.instantly.ai), primarily email sequence software, but also allows sourcing leads by some parameters, Thank you!