Northern Leasing Systems, Inc Harassment and rip off New York, New York

Northern Leasing Systems Inc. Has been harassing me on a daily basis..I was put through to this company through TransFirst credit card services for my equipment.I agreed to pay them $31.98 per month but ended up paying $36.93 per month as I am being charge an extra $4.95 per month for taxes and Loss and Damage waiver fees... I was also charged in July of 2010 a fee of $25.00 for my 2011 taxes on my equipment $5.00 was for the equipment $20.00 was for service fees...then in January 2011, I was again charged $27.00 for my 2012 property taxes $7.00 was for the equpment $20.00 was service fee...I cut them out of my auto pay and have been paying them by check and they now want to charge me an extra $5.00 per month to process my checks..I send the checks certified mail so as to make sure that they receive them...I have not paid the extra $5.00 per month that they request and refuse to do so as the certified mailing cost is $5.59 to mail them the check..I feel that is fair trade..so now they call me daily for the money they claim I owe them..a $31.00 dollar payment is expected though I have not sent it nor will I.