RED FLAGS!! Arrogant sales agent and no contract before payment is expected.

Received a quotation from this company, then when my family and I called to ask further questions about how the invoicing, payment, installation, and service agreement would take place, the sales agent Anthony, started being rude, saying he wouldn't answer all our questions and hung up the phone. He stated that they expect us to pay them 60% upfront (before any work is done and before a signed contract), then only can we see the service agreement (contract) and have the technicians dispatched to install the system. My advice is to save your money and preserve your peace, don't bother working with these guys. If they disrespect you on the phone before payment, you can only imagine the stress that will follow once you work with them.