Under which Scheme(s) should we register?

My wife and I have just moved to France and have bought a house.  We have a small interior design & lighting business based in London but which operates internationally, mainly online.
Around 80% of our work has so far been in the UK but this is likely to change as the online business develops.  However, whilst most of our working lives have been in London we are Irish citizens.

We design the interiors and lighting schemes and supply all the necessary furnishing and technical hardware to enable lighting control, etc.  Most of this is sourced in the UK and despatched direct to the client as we are resellers for the major manufacturers.

We intend to transfer the business base to our home in France and register under the French system. 

At the same time, I have now reached retirement age in the UK (I am 68) so have adopted retired status and draw the UK state pension plus a small private pension.  I have an SI form and have been advised to register as retired in France to benefit from the French healthcare. 

My wife, who is ten years younger than me will continue to run the business from France as on online design service but still supplying as required. So it seems she should register as an Enterprise Individuelle Reel Simplifie in order to benefit from the tax and VAT concessions associated with the buying and selling of products for resale.

She intends to continue this business until she reaches retirement age.  It is also our intention to create two or three chambre d’hotes on one floor of our house as a secondary income.

So, my questions are as follows:

1. Is the Enterprise Individuelle Reel Simplifie the right correct scheme?

2.  If the income from the main business reduces and the chambre d’hotes take over as the primary source of income, do we need to change the status and register under a different section?

3.  Can I assist with the chambre d’hotes and/or the original business on an unpaid basis without registering?  If not, how should I register and will it affect my retired status with regard to tax and health insurance? 

Thank you.