Depends on the DIYer, requires a torx bit set & about 1 hour.
WE rarely replace the complete latch($350. each) but only the hydraulic cylinder($140. each)

Make sure to use the correct fluid & to top-off the fluid.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator