I'd agree with all the info given so far. But I'd also start with a question: what do I want to achieve with my own website? I suspect ultimately you'd like to increase your bookings but creating your own site on its own probably won't do that. However linked in with an overall marketing plan which will take into consideration your social media presence, your listings on other websites, your blogs, your local networking etc it probably will.
If you're really keen to find out about web marketing this book's a good read Digital Marketing
Brian will give you a better idea but I'd budget about €200 per year for someone to put together then maintain and host a wordpress (or similar) site. This is a very rough figure, but I'd definitely advise having someone do it for you unless you're particularly savvy in this field.
In terms of transfers into a French account, that shouldn't put anyone off these days. My UK business and personal accounts offer this service online at competitive exchange rates and for a small fee (£5 I think) or you could get your web designer to integrate paypal or google checkout into your site which is even easier for customers but will cost you maybe 3% or so.
Hope this all helps :)