Contact Markettrellis
The form takes a name, an email, and a message. Markettrellis keeps it as a private note. It does not sign you up for Mailchimp or HubSpot.
If a price here is wrong, say which page and what the company's page shows now. Mailchimp Standard at $20 for 500 contacts, and HubSpot's $20, $890, and $3,600 starting prices, are the lines worth checking.
Don't send a password or an API key. A billing dispute with Mailchimp or HubSpot belongs with them. There is no promised reply time.