Commercial shops are great, but as others have stated ... come with a unique set of issues. One being overhead, almost every utility for a commercial store front is higher ... Just the breaks. Next being your location, some locations are great for customers to visit you, but not really businesses, some are great for businesses but you lose normal retail customers. The next is survivability, how do you get your name out there past the work you are doing and hoping someone name drops you (word of mouth advertising) or trying to ticket an area with guerilla marketing (yard signs, brochures, etc)? ... you may have to have an outside sales person just to get foot on ground for you.
Home based is a different set of issues, more personal foot traffic, slower sales, zoning restrictions, neighbors hating your noise you produce, etc, etc, etc. But ... overhead is drastically different. You can share your internet with your house, go almost completely mobile with a dedicated cell line, etc etc etc.
I personally dislike commercial locations ... but that is because of how the market is at the moment ... plenty enough work to go around ... it's just getting redonkulous with the zoning reqs on new signage, the customer flow of areas is odd, and even though there are constant start ups in town to get graphics/signs/awesomeness/whatever done ... the customer perceived value does not cost expectancy.
That being said, I'm in the process of starting up my own shop again ... pretty unavoidable really. But the way I will probably do it will be based out of my garage (a seperated building with it's own breaker so I can technically put a second meter on it for tax sake.) which I can do larger graphics in, and sign production and have a small mobile graphics unit out of a trailer for onsite graphics production and install ... nothing big, maybe a small desktop sized prismjet from signwarehouse and a plotter to match ... hey ... it's perfect for a trailer, don't be a judgy pants mcgee.
The way I see it in your question OP ... look at long term projections ... with a retail space, it's a monthly payment and if location sucks or clientel moves ... you can't change it for what 6months to 2 years at a time? ... ouch. build on your property, 5 years it's paid off ... if you still want a retail shop ... look into it then ... you always have something to fall back on if the retail shop eats it like a bag of monkeys.