I ran into something similar last year trying to organise a mess of warm contacts across different platforms.
For your setup, Hubspot Free should work fine as your main warehouse since you're dealing with under 1M contacts. The main limitation you'll hit is workflow automation, but for a one-time data consolidation and some basic segmentation, it's perfectly adequate.
On enrichment, given you already have QuickEnrich credits, just use that. Apollo's fine too if you're already familiar with it. The differences between tools matter way less than actually getting this done.
For combining the data, honestly I just used a combination of Google Sheets and some basic Python scripts. Export everything to CSV, dedupe by email, then run enrichment. The LinkedIn export is usually the messiest part because of how they format message history. I found it easier to manually flag my top 100 warmest connections rather than trying to automate sorting through thousands.
One thing I'd suggest is manually reviewing anyone who's engaged with your content in the last 90 days on LinkedIn before you enrich the whole list. Those people are probably your hottest leads and worth prioritising first.
What's your current relationship like with these warm contacts? Have you been nurturing them at all, or is this more reactivation?
