Make that in the email adreess appear in the subject of the emails received in my Gamil account from the contact forms received from my sites set under Magnto. In that way each subject will be differente so Gmail will assign one conversation per email. Even better if you can add a counter in the subject.
Dear Friend, Once you see your customer's email coming in the subject while they submit the contact form and you received email at gmail account so then you should pay us before that we do not require any single Dollar from your side. Please check our private message we are magento certified developers and designers. Many Many Thanks
Dear Buyer!
We are ready to start working on this project, please check the PM for details and our work experience.
Regards,
Project Manager,
Platonic Solutions