Dodgy condensate pipe?

[GrahamM]

The condensate should terminate into a proper waste water drain or into a soak-away under ground level to comply with regulations.
There are many means at the installers disposal and it would be unlikely a proper method of complying with regs would not be available to the installer. He is just being lazy/incompetent/negligent.
As mentioned the condensate solution is normally in region of 3-5 pH and my car would not be anywhere near this.

 

[TBServices]

It can be damaging.

I once saw a flue project out of a side wall on a small terrace, directly onto a steel lamppost about a foot away. It had eaten a huge hole out of it. This is essentially the same stuff (in liquid form) that had eaten away the lamppost. Tell your neighbour to get it sorted.