Netherlands-based company Derks specializes in two main things: stretch limos and catafalques. The Tesla Model 3 depicted here belongs in the latter category.
Originally a Standard Range Plus spec (see video), the electric vehicle was extensively modified with a longer wheelbase and new bodywork. Despite the added bulk, Derks claims the driving range still manages to exceed the OEM-promised 322 km (200 miles). Nice additions to the cabin include an illuminated headliner and more LED lights at the rear end. The tailgate and the special curtains on the windows make use of standard-issue servomotors to open and close.
The company does not mention any pricing details anywhere, but we saw a similar project based on a Model S a while ago. It cost north of $200,000 USD.