I have a general know-how, as under....
(1) I have said that we are required to get the car re-registered by paying tax afresh (and seek refund of life-tax paid at Gujarat). But in my 2nd para I have said that transferable people generally do not pay tax afresh, and that, there isn't any problem as such. Regarding penalty, as I understand, it is in % terms of the tax payable and it varies from state to state - I have heard that it ranges from 20% to 50% (of tax payable).
(2) On re-registration (in new state), the car registration number changes.
(3) If octroi is applicabe to Delhi, it will be payable - as applicable to old cars in % terms based on its valuation.
(4) Other than Toll tax (as & where applicable) no extra tax is payable if private cars are driven from one state to another, except Octorio (if applicable (point #3).
(5) Octroi is payable, if applicable, even if the car is transported through truck.
By the way, as I understand, Octroi (whereever applciable) is not applicable on some (?) house-hold kit on transfer - a certificate from the employer is required. However, if recovered, refund could be claimed.
Importantly, if you are getting transferred in a couple of months or so, like you have said earlier, I feel it would be prudent to postpone your purchase so as to avoid re-registration (as per rule) or, if you are not re-registering it (against rule), to avoid even the possibility of paying penality. Octrio, if applicable in Delhi, will in any case be payable by you - a little less, of course, if transported from Gujarat (2nd hand car / almost new).
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