David Wilson Homes is currently building 36 houses at Station Approach, off Ongar High Street, and a three-storey mother and baby unit comprising 14 flats.
Now retirement home builder McCarthy & Stone wants to build an additional 60 private, self-contained assisted-living apartments for the frail elderly, leading to concerns about overdevelopment.
Ron Frost, a resident of Bowes Drive, said: "I don't think they should have been allowed to build anything there in the first place.
"People around here objected, but it made no difference."
The elderly homes development would comprise 45 one-bedroom and 15 two-bedroom apartments and would be staffed 24 hours a day.
Neighbours claim the combination of the developments will create a dangerous situation on the surrounding roads and fear there will be a steady stream of cars pulling out onto the already busy High Street.
Problem
Chris Jackson, owner of Station Garage, said: "It is difficult to get off this courtyard. Sometimes you have to wait five minutes to get out.
"And I think it will be an even bigger problem for the people trying to leave that site."
The proposal is for 25 parking spaces, including five for the disabled and a mobility scooter store for the elderly residents of the complex. However, the developers have insisted they will not add to the congestion.
A McCarthy & Stone spokesman said it would not share the same access as the David Wilson Homes project. Instead, it would have its own entrance and exit just past Bansons Lane.
She also said the majority of residents would be in their 80s and unable to drive, before explaining the location is ideal for the elderly as it is close to shops, services and public transport.
McCarthy & Stone is undertaking a pre-application public consultation exercise with neighbouring home and business owners.
Residents should have received a briefing pack containing details of the planned development and a comment form for their views.