I don't use a "CRM feature to manage customer relationships." I just try to keep all the photos of my work in a simple, organized spot so I can find them later. The "radical approach" was a simple, human one.
The process I had to completely reimagine was how I kept track of my jobs. For a long time, I was just taking photos on my phone and they were all a mess. When a client would call me back for more work, I couldn't find the photos from the last job. It was a complete mess. I realized such a radical approach was necessary when I started looking unprofessional because I couldn't remember a job. I knew I had to change things completely. I had to shift my approach from just taking photos to organizing them.
The single, specific "feature" I recommend is just a simple folder on your phone or a Google Drive folder. Every time I finish a job or a client sends me a picture of their electrical problem, I put it in a folder with their name on it. It's not some fancy "platform" with a bunch of buttons. It's just a simple, common-sense approach. The "feature" is just a folder.
The impact has been on my company's reputation and my own sanity. By keeping everything organized, I'm able to look more professional, and I can easily pull up photos from past jobs to show new clients. It has saved me time, and it has saved me a lot of headaches. A client who sees that I'm organized is more likely to trust me, and that's the most valuable thing you can have in this business.
My advice is simple: don't look for corporate gimmicks. A job done right is a job you don't have to go back to. Be organized. That's the most effective way to "manage customer relationships" and build a business that will last.