Were there any challenges with shipping, customs, or delivery?

With a 4-unit building, that’s a very high customer concentration.

Is there a certain direct mail service they prefer?  

Quote from @Brandon Weis: In your opinion, as you are starting out at 0 reviews, do you think it is a must to beat the competition on price to overcome customer's hesitancy or lack of trust with no reviews?

If you’re passionate about windows and doors, you should naturally have plenty to share based on your expertise and the questions your customers ask.The main purpose of your blog should be to educate and provide value to potential customers.

This allows them to get more capital so they can make more loans without having to grow their asset base, while also maintaining their relationship with the customer through monthly payments.

There are more customers than ever right now on any platforms.

While trying it out, call their customer service and see how they treat you and how knowledgeable they are on their product.

I look forward to hearing from you via email  or if possible, I'd really prefer a phone call. 

Customer service from a support perspective matters of course, but no hang up or delays on investing would take place.