Business relocation from the UK to France?

I am a freelance IT trainer business in based France. I have been trading through a UK limited company. My main clients are based in the USA, India and Germany. I have purchased a property in France and am now a full time resident here. I need to relocate my fiscal base from the UK to France as a result. I am now doing an increasing amount of work online from my home in France with the remaining work involving business trips to Germany, Switzerland, UK and USA.

1. The business trips often incur considerable expenses and I often have to quote an all inclusive rate for my time and expenses to the client. I would need to offset expenses against taxable income. What is the best option for setting up such a business in France?
2. I had to deregister my UK company for VAT as the bulk of my turnover was from non-UK companies and VAT was not chargeable. What is the situation in France for TVA?
3. I did work as an IT contractor in Paris in 2004/2005. I was registered as a freelancer in France during that time. I no longer have any documentation of this. Will I still be in the system?
4. My partner and I purchased the French property with a view to setting up a chambres d’hotes. Do we need to have separate businesses, or it it possible to use a single business to cover both activities?