Firstly lolage, welcome to Focused!
I would also like to take this opportunity to offer your granddad a free domain (.com) and life time web hosting account on behalf of Focused and Alloy Hosting. Please open a sales ticket at alloy referring to this ticket and we'll get you setup!
I would like to mention that an online presence on the internet can help improve the overall business image to current clients and potential, both local and alien (from other cities). An example would be if some one was looking for a certain brand of fireplace and they found your shop from natural organic searches in the search engines. They could find the details online and either start a live chat (Using Live person or a range of other software) call or email (which could be piped to a ticket system for better management).
Also, services like Google, Yahoo and other major players in the searching industry offer services related to their maps. E.G. If you type in Google Fireplaces in London (Click
here to see) they will offer a list of local businesses in that area offering what you are looking for. This could help your granddad get a lot of local potential customers near by.
There is always the option of taking it further one more step. You could setup an online commerce site (there are pre-installed scripts with Alloy Hosting's Fantastico) which would allow him to start selling online. This would increase his market that he could appeal to, and will allow him to target potential alien customers out of his city / state. Services such as Adsense could be used on a pay per click basis. If you make those campaigns well, they can make you 1000% ROI (Return of investment) figures from $1-2 investment. Another option would be to find a company that you can purchase leads from. You would pay them say $40 for example, when they send some one to your website who is interest and fills out a sales email / ticket. If you do decide to venture online, you could setup an affiliate system for your existing customers which will allow them to send links to friends and family. If they generate a sale, you could give them 5% for example.
If you do decide to start an online commerce site, it would be a good idea to make business accounts with couriers such as Fedex, UPS etc. I would stay within the country you live in to start with, not offering international sales until you have the money and sales to ship items that far.
Another option is eBay. eBay have a built in feature for stores and the market is already there. Every hit you get will be targeted as they have searched for that item. It is fairly cheap to list, but on top of that you have eBay's final selling fee and if you decide to go with paypal, you have paypal's percentage to pay as well.
I hope the information has helped
.