mate, I've been around the block with both paid and outbound. Sending 1,000 cold emails a day from your primary domain? That's an one-way ticket to the spam folder, if not a full domain blacklist.
One colleague tried this with a fresh, pre-warmed domain-still got burned within hours. The providers you spoke to aren't being overly cautious, they're dead right. multiple domains, multiple inboxes per domain, slow warm-up over weeks.. it's the only way if you value your deliverability.
I've seen setups using 5 domains with 6 inboxes each, sending maybe 30-50 emails per inbox per day after a proper warm-up. Even then, you're monitoring bounce rates, reply rates, and spam complaints like a hawk.
If you want to scale cold email without poisoning your main domain, treat it like you would a Facebook ad account-spread the risk. Don't put all your eggs in one basket. Your primary domain is your reputation capital, don't spend it on cold outreach.
for platforms, Instantly and MailerLite are solid, but you need to manage the complexity. No shortcuts here.
