Services
Real estate · Smart home · Energy
Our services
Kofen Chang leads the real estate work, supported by JoyfulHouse's in-house smart-home and solar engineering practice.
Real estate
San Marino · Arcadia · Pasadena · Temple City · San Gabriel · Alhambra
Real estate guidance.
Kofen Chang provides buying, selling, and investing guidance across San Marino, Arcadia, Pasadena, Temple City, San Gabriel, Alhambra, and the wider San Gabriel Valley.
- Negotiation backed by MBA-grade analysis
- Bilingual service (English · Mandarin)
- Neighborhood-level guidance
- 88+ transactions closed
- REALTOR® · CalRE# 01951860
Smart home
Home Assistant · open source
Intelligence that lives at home.
Design and installation of AI-integrated automation — language and vision models run on hardware in your home, so voice, cameras, and daily routines stay private. Local-first, no subscriptions.
- Local-first smart-home design
- Installation without subscription dependencies
- Open-source software maintained in public
- 17 open-source projects
- Software used by real homes, including ours
Energy
EG4 certified · Solar + storage
Solar and storage.
JoyfulHouse provides solar and storage system design, monitoring, and integration.
- EG4 certified installation
- Solar and storage system design
- System monitoring
- Smart-home and energy integration
- In-house engineering practice
