Legal structure for secondary business activity in France?

My gites in business in France is registered with with the chambre de commerce as micro-entreprise professionelle. I would now like to work again as goldsmith as my secondary activity. I believe that auto-entrepreneur is not an option for me as:

• I cannot deduct costs (which will be fairly high in my metier) from my turnover.
• Being registered with the gites I cannot have a second activity where I would write invoices to clients so need to be an employee (and patron) at the same time.

Is this correct?

In order to keep my set-up costs as low as possible would it be advisable to start as an enterprise individuelle. The question here is to operate under which regime: micro-entreprise, bénéfice réel simplifié or bénéfice réel? Then change maybe at one point to SASU (IR) and pay myself in dividends? At which point would this make sense?

My questions regarding enterprise individuelle:

1. Do I need an accountant, e.g. for profit and loss account, and would the fees be similar to those in EURL or SARL (€1800 to 2000 euros per year)?
2. I cannot find information about how much income tax has to be paid on the profit.
3. I know as an enterprise individuelle I would need to pay social contributions to RSI (around 40% of profit). In case I do not make any profit I believe there is a minimum payment to be made. How much is this?
4. Is there a turnover limit?
5. Do I have to be registered for TVA?