I don't think you will get anywhere with saying to a seller "well because you lied to the IRS, I think I should get a discount on the property."

If you don't have MLS access and know how to comp properties this is a skill really worth learning and there are lots of youtube video that can help with this.The value of wholesalers is your ability to buy at a discount and that can be a huge asset building your portfolio if you add to it the knowlede of comping properties and estimating your rehab accurately.  

From your assessment, what % would be a fair discount ?

A lot of people throw that term around here for agents and title companies, and it can sometimes mean "someone who will do things I want at a discount/free because I tell them I am a real estate investor".

I recently got pre- approved for a mortgage and will be moving in with my girlfriend who has a cheap rent stabilized apartment, which will allow me to safe a lot of money.I want to invest in a condo as a rental property in nyc, i realize i probably will not get as much cashflow or find a 20% discount price that is recommenced in the bigger pocket book because the nyc market is tuff to make some of the advise in the bigger pocket book work.But i realized i can kind of force the cashflow numbers to work if i put a larger then 20% down payment on the mortgage,which i am capable of doing If i go with this option i will only be able to afford a studio condo 300-350k price range that will dated and need some reno work that i would be capable of doing myself.

Additionally, he now provides a discount for my recurring business which is always good!

I would let them have the option of a 2 year lease w/ no discount for all the reasons you mentioned.

Granted, if you have a great relationship/high deposits with one of the Big 4, you may get a decent discount on rates. 

I know I have to give full disclosure to all parties - just trying to stay within the law but still find discount sellers and investor buyers.  

Do we get a discount for doing multiple properties?