A: Great question, and yes, you can absolutely get emails for 5,000 contacts.

On the credits: Email enrichment costs 1 credit per successful email found, and failed lookups cost 0 credits. So 5,000 credits covers up to 5,000 found emails. Because misses are free, you can actually run more than 5,000 contacts through and only pay for the ones that resolve. Worth noting: on Tier 7 you also get 2,500 one-time credits (which never expire) on top of the 5,000 monthly, so you're starting with 7,500 to work with.

On the 500 limit: That 500 is the max contacts per list, not a cap on how many contacts you can enrich total. Tier 7 includes unlimited lists, and your credits are one shared pool across all of them. So yes, your instinct is right: split your 5,000 contacts into ~10 lists of 500, and enrich each one. Every list draws from the same credit balance, so there's no downside to splitting other than the extra uploads.

One shortcut: Since Tier 7 includes API access, if you'd rather not split manually you can enrich via the bulk API instead (up to 250 contacts per request), which skips the per-list limit entirely.