Rent Overcharge: Substantial Improvements

[elgaumer]

I am currently in a rent-stabalized alcove studio and have a sneaking suspicion that I am being overcharged. Here's the short of it:
Rent History: last registered rent pre-vacancy lease was $400. I came in in April 2000 at $1725. There is a discrepency between what I pay and what is "registered" with DHCR--about $200 (it's registered higher than I pay).
The justification of the rent increase is the 18 percent for a 1 yr lease plus $50,000 in renovations (Keep in mind that my apt is 275 square feet).
There is also an MCI application pending which would raise my rent by $50/month.
That's the easy part...
Prior to my moving in (mine was the only vacancy) the building was gut renovated. This was actually completed because the other tenants sued the LL and the court mandated building-wide improvements. The courts mandates included replacement/update of kitchen, bath, heat, gas, electric, structural, etc.
I know that the LL can do these improvements to my apt without consent since it was vacancy, but my questionS ARE THESE:
1. IF THE IMPROVEMENTS WERE COURT MANDATED, ARE THEY IMPROVEMENTS OR SIMPLY REPAIRS?
2. IF THE IMPROVEMENTS TO MY APT WERE THE EXACT SAME AS OTHER APTS DOES THIS AFFECT THE INCREASE?
3. CAN ALTERATIONS THAT AFFECTED THE ENTIRE BUILDING BE CONSIDERED IMPROVEMENTS TO MY APT AND THUS BE CHARGED FOR THEM?
4. IF I SUE FOR RENT OVERCHARGE, HOW CAN I PROVE THAT 50K WAS NOT PUT IN TO MY APT IF HE HAS 'RECORDS' PROVING THE REPAIRS COST THAT? CAN I REQUEST COPIES OF PAYMENT IN COURT OR ACCOUNTING RECORDS OF THE CONTRACTOR?
There is, of course, even more, but I'll keep the questions to the main ones.
Thanks!