Rent history requested- shows 4 consecutive vacancy incr

[oyster]

I requested lease history after the suggestion to do so. Not too familiar with stabilized laws, but thought does not hurt. I receive back the information and this is basically what it shows as far as rent history the approximate values for the following years:

1998 $885 LEAS/RNL
1999 $1045 VAC/LEAS
2000 $1235 VAC/LEAS
2001 $1455 VAC/LEAS
2002 $1715 VAC/LEAS
2003 $1785 LEAS/RNL
2004 $2090 VAC/LEAS
2005 $2150 LEAS/RNL
2006 EXCEPT High Rent Vacancy

No prefer. rent or actual paid rent information was disclosed on the form.

It appears between 1998 and 2002, the unit had four consecutive vacancy increases, and actually five in a six year period. These large vacancy increases apparently pushed the legal rent price high enough so it could be made an exempt unit. Are multiple consecutive vacancy increases allowed? Even if not, is this too long ago for anything to be done? Thank you so much for any insights you may be able to offer.

[TenantNet]

Once you get a DHCR rent history, you need to compare it to allowable RGB increases.
Were there any listings prior to 1998?
Look at the RGB orders for each year to see how the vacancy increases should have been figured (the method has changed over the years).
There are also longevity increases (for long-term tenants) and IAI improvement increases.
Generally, one vacancy allowance is permitted per year. If you had three vacancies in 2015, each must be figured on top of the 2014 rent. So the vacancy increase would be applied to the first vacancy, but not the other two. This method did change for a while, but I believe it's back to one per year.
The deregulation trigger was $2,000 up until 2011. Now it's 2700.
And unless you can show evidence of fraud, overcharge claims are limited to four years. However RS status is not limited to the 4 year SOL. So if you can show the rent in 2006 was not legally above the $2,000 trigger, you can get the RS status back (but can't collect overcharges).