Accommodation
There are many, many hotels in Paris. These are a few you might consider. In hotels on busy streets you can ask for a room facing the back.
Nearby the conference/workshops site (5-12 minutes walk)
Nearby Gobelins metro station (3 metro stations with line 7 from the conference/workshops site, or about 20 minutes walk).
On the cheaper side. (From 25 euros, dormitory-style accomodation, about 25 minutes walk from the conference/workshops site).