Hi,
I have experience for 15+ years in electronics/embedded development.
I have several years of advanced AVR/arduino development, including library development from scratch. Practically all Arduino AVR boards used, like: 2009, 2010, UNO, MEGA, NANO, MICRO, MINI, etc. Several shields used like Ethernet (W5100, ENC28J60, etc.) with various IP protocols implementation, various graphical TFTs with and without touchscreen and various BUS types (parallel, SPI, I2C, etc.), all kinds of sensors and buses, serial and parallel memories, etc.
I didn't get by your project description what you intend to do, but by your sketch, it seems you are trying to connect a matrix keypad to an arduino ? I have worked several times before with matrix keypads and will have no problems implementing this.
Also, I didn't get what you mean by "To make a connections between PC and electric house devices.", we can discuss this further, I guess...
If you are interested in my bid, please let me know some more details about your project and I'll be able to answer you back telling if I'm up to the task or not. Feel free to contact me.
Regards,
Carlos.