Not sure how old you are but from my experience I wanted to do the same with the PC side of things; but I got bored with the 'hardware' side of things really quickly.
I wanted to setup a business doing repairs for the home users, but what held me back was the ever reducing cost of laptops in the retail market - I'm sure people will quote macs at me and top spec laptops, but generally these devices are becoming disposable, but now the market is turning towards mobile computing, in business and home, and therefore I feel that the days of the home laptop user are numbered.
I started out wanting to fix laptops and PCs, but where do you go from there? No room for improving your skill set in my honest opinion.
In my current workplace, a laptop breaks - buy another one or get it on a 3 year warranty.
A server breaks, we have a care plan so HP come and fix it for us.
Laptop playing up - we have a server which installs everything for us automatically, plug it in and leave it. It all comes down to cost reduction and time saving. So in the end me stripping a laptop down to replace a motherboard is not a good use of my time or the companies time - so we crush it and buy another.
I'm not putting your dreams down there, as much as It may sound that way, I guess it you're after happiness go for it, if you're after making a lot of money, I'd rethink if a bit.