What I'm sure of is that you can't get that particular parking lot back as it was never owned by the vendor in your case in the first place. Nemo dat quod non habet - "he cannot give what he does not have".

If you were so particular about that parking lot you ought to have asked your lawyer to call the JMB or developer's office and make sure that the particular lot is the corresponding lot in the principal SPA with the vendor. Have you asked your lawyer with regard to the predicament you are in?

If you want to start suing your avenue is against the vendor, who will in turn sue the developer, etc etc etc. An utter waste of time and resource as you surely cannot get back that particular lot.

Best to just swallow the bitter pill and move on. 

Ok now the facts are clearer, although not 100%. So the Nemo dat quod non habet - "he cannot give what he does not have" - principle will be applicable in your favour as the developer cannot purport to sell it to another person (the neighbour) when it has sold it off to the vendor in the first place. So the purported sale to the neighbour would be null and void and of no effect. So my earlier advice would not be 100% applicable, in light of the factual matrix which you have just stated above.
It's breach of contract by the vendor against you. It is not fraud though. Don't merely use the word fraud as it is a bigger word than you think. It is not easy to prove fraud and in this case, from the basic facts stated, I doubt if the vendor is a party to fraud. I'm sure he is as ignorant about the purported subsequent sale as you are.
As explained earlier - you sue the vendor for breach of contract - the vendor will subsequently bring the developer in as a third party, and perhaps the neighbour as well. It's messy, and would cost you quite a bit of money in legal fees as well. Whether or not you can recoup the legal fees from the other parties in this case once it's over is another issue.

If you're going to reside in the unit after this, bear in mind that going on the warpath against the developer and your neighbour, albeit indirectly, may not be the wisest option.

However, if you are going strictly on the principle that you ought to get what you paid and contracted for, then by all means go all out to get that parking lot assigned in your favour.

From the facts presented herein, you do have a good case. The neighbour's remedy would be to sue the developer for damages only, as he can't get back the parking lot.

I'm going to pre-empt you at this stage before you ask me and inform you that legal fees for litigation (court) matters are subjective and differs from firm to firm. There's no market rate, usual rate, normal rate, etc etc etc. So if you want to find out, you need to see a litigation lawyer, set out your facts, and ask for a quotation for legal fees.

I wish you all the best.

That's the thing - you can't quantify the damages as you did not suffer any actual loss. You need to prove your loss. If there was no parking lot available and you had to rent out another owner's lot, then yes, you can quantify the damage suffered, i.e. rental x number of days = loss suffered.

In this case another lot was offered to you, albeit at a further distance from the lift. What loss have you suffered which can be quantified? Hope you get my point. You can get a lawyer (and i'm sure there's a lot out there) who can promise you the world and convince you that you can get lots of damages, but at the end of the day, I'm of the opinion that if you can't quantify it, you can't claim for it.

Inconvenience, extra walking distance, anger, frust, stress, mental anguish, distress etc etc is all just hogwash and no judge will entertain a claim for that.

As such, your primary claim would have to be for specific performance, i.e. to assert for ownership of lot A. Damages would only be a remedy if specific performance is impossible.

That is all the opinion I can render. If you wish to go further in this you'd better seek proper legal advice from an actual lawyer 

All the best. Do keep us updated if you proceed further in this case.