How can I start a retail repair station?
You will need to find the site, get your permits, then start getting customers. Remember that acquiring things like the permits are the easiest part--it's the attracting of customers that will take the most work.
As for doing it more as an investment, take a look through brokers and websites to see if there are any already running in your area for sale. You may be able to buy it and hire a team of people to run it for you from day 1.