Read AD’ s June cover story on Nate Berkus and Jeremiah Brent's house in Portugal here . At this point in their careers, Nate Berkus and Jeremiah Brent have stopped counting the number of homes they have renovated—both for themselves and on behalf of their many clients. But as the AD100 designers discovered while restoring their new vacation house in Portugal (see AD ’s June cover story ), there’s something new that even seasoned veterans can pick up every time. They admit that they didn’t realize how challenging the project would be—from the logistics of working in a remote corner of Portugal to the intricacies of farming and land stewardship in an unfamiliar climate. “Trying to get the details that were important to us from miles and miles away was a constant source of stress,” Berkus says. Was it worth it? To them, absolutely. Here, Berkus and Brent share five takeaways from the five-year project. A quartet of sheep roam the property.…