I've said this about 'flying cars' - but it applies equally to 'helo cars'.
The needs of a good car and something that flies are dramatically different and fundamentally incompatible. You can build a good car, or you can build a good airplane/helo. But as soon as you try to combine them, you're going to end up with something that is so horribly compromised that it's going to suck at both being a car and an aircraft - and something costs as much as a good car and good aircraft combined...