I work in Property Management and my advice would be to know exactly what you’re getting yourself into before going ahead. Leasehold isn’t the problem, the issue is that most people get into it not knowing exactly what they’re signing up to.
A house on a residential development be it Freehold or Leasehold will still be obliged to adhere to the covenants within the lease. I obviously don’t know the specific development you’re buying on but it could be things like not making noise outside of set hours, not being allowed to change the colour of your front door, gardens must be maintained at all times, no increasing the height of garden fences, no storing items in the front garden etc.
With regards to costs, you need consider exactly what is in the car park. You don’t mention the size or that it’s secure but there could be gates, intercom & access control systems, cctv cameras, fire alarm systems & extractor fans, emergency lighting, drainage, bike stores. All of this equipment, if it is there, needs maintaining and eventually replacing. It’s the residents collective responsibility to pay for this.
In addition to this, if the roads aren’t adopted then you are required to pay for the maintenance of the estate areas. This could include maintaining street lights, cleaning the street areas, communal landscaping, winter gritting etc.
The lease probably also allows the landlord to introduce additional services which you may need to contribute to. As an example this could be security patrolling the estate if it is needed, you would benefit from this, therefore, you have to contribute to the cost.
The person who asked about bins, the cost is not normally for the collection costs as you are correct this is covered by your council tax. The costs are usually for the hire and the maintenance of the big communal bins.