Roofers usually ask for a part of the money upfront before starting a job. That's because they need to make sure you are committed to working with them, and you will not back down. Also, that money is generally used to buy the materials and supplies they'll need to do the job. But the sum shouldn't be too big of a chunk of the total price. If roofers do that, they have more jobs simultaneously, and they need the money to get them done. You don't want to end up having to pay for someone else's roof.
Also, trustworthy roofers don't ask for a lot of money upfront because they know they are the ones you want to do business with. Many new and inexperienced roofers tend to ask for a lot of money upfront from their clients. Many people tend to steer clear of such roofers and prefer to work with more experienced ones. The amount of money asked upfront is a good way of telling how reputable Highlands Ranch roofing companies are and how sure of their skills are.
An experienced roofer will ask for a down payment that doesn't exceed 50% of the project costs. The money you pay upfront shouldn't exceed the cost of the supplies necessary for the job.