Change auto-entrepreneur to SASU and social/health coverage

Dear Valerie,
thank you for your guidance regarding different structures and options for small business. It is very helpful, specifically for people like me with completely different educational background which is “far away” from economies/finance/accounting.

I eventually came closely to the idea of either having:

• Auto-Entrepreneur and SASU at the same time (however activities should be different).
• Change auto-entrepreneur to SASU in 2018 ( I will be at 35K soon) which seems reasonable. However, with this option of having SASU, waiting for dividends and not paying social charges, there will be no health coverage. My husband is on CDI contract in France with very good health coverage package. When I was not working as auto-entrepreneur, I was covered as his dependent and it was very simple and efficient in terms of reimbursement. As soon as I became registered as auto-entrepreneur, it was cut, became very complicated and I still have not received my carte vitale.

I am wondering, if I go with SASU with no salary, would it be possible to be covered under my husband’s package as a dependent and what should be done to get this status if possible of course?

If I open SASU during 2018, as I understand -  in 2019 I will pay the personal income tax on the dividends for the 2018 and incorporation tax (for the company) appr 15,5%  up to 38K. I am expecting an income for SASU in 2018 up to 30K. How the dividends are calculated ( sorry for asking basic questions…) and can I transfer dividends from the year 2018 to the personal account in 2019 and use for living.

I have a professional account for auto-entrepreneur with some savings on it; if I close auto-entrepreneur status, can I use it for SASU (already with the savings, part of which can be used as a start capital) ? Conversely, can I have the same professional account for auto-entrepreneur and SASU (if I decide to keep both auto-entrepreneur plus SASU) ... probably not..

Thank you in advance,