How to reach 2000 contacts over mail?

Hi Everyone,

So I run useinstaleads.com where we help agencies, saas founders, freelancers with the contacts for their potential clients.

I have about 2000 leads that fit into my ideal customer profile and I wish to reach out to them via mail. I want to set up an entire email funnel instead of reaching out to them 1-1. Which are the best tools to implement this? Mailchimp, sendbird etc would be too costly.

If someone has done this at some cheaper rate but efficiently, would love to know how you went about it.

As a token of appreciation, I'll send out a curated list of 100 startups with their details including email IDs for your business.