If ITC on the car was not availed (which is common, because ITC on motor vehicles for personal use or passenger transport is blocked under Section 17(5)), then you can apply the margin scheme;
Margin Scheme (Rule 32(5) of CGST Rules)-- If ITC was not claimed, GST is payable only on the margin amount of Rs. 90,000/- in your case at 18%.
If ITC is claimed, then on entire amount of Rs. 5,90,000/- GST has to be paid, despite blocked credit.
If it is transported, e-way bill is required.
E-invoice depends upon turnover of Rs. 5 Crores and above.