Not without the bank signing off on it.

Problem is only "RE pros" get to do it.There are 3 income classifications in the US - Active, Portfolio, and PassiveActive income is income derived from your job, or normal trade or business.Portfolio income is derived from bank instruments - stocks, bonds, etc.Passive income is income earned from investments.Active losses can wipe out both passive and portfolio income, but it doesn't work the other way around.Portfolio (capital) losses are limited to $3,000 annually.Passive losses can only be offset by passive gains.Real estate rental income by its nature is deemed passive per IRC Sec 469One way to get around it is to become a pro - spend more than 750 hours or 1/2 your time in real estate.But most folks aren't real estate pros.

After my internship this summer I will have about 20k in the bank. 

How seriously is it enforced2) Who will do the transfer, do we have to tell to the lender or the bank?

If you can find smaller local banks in the market you pick they may have more unique products that they keep on their balance sheet or try and do the 5% down conventional on a 4-unit  FHA's self-sufficiency test applies to both 3 and 4-unit properties.

How does one take the owner finance situation to a bank and turn it into a 30 year loan to hold without an additional down payment of 20 percent ?

I have an assistant enter this once a month from the PM reports provided (and just a bank account statement for the single tenant properties which don't have PMs).

Given the seasonality there's likely slow workflow from the banks so it would be a good for you to apply, get approved, and be well poised for the spring market!

Virtually all 5+ units in Reno where the buyer is using bank financing will require 50+% down.

You'll want to make sure multiple banks look at the deal to see general appetite for financing.What happened to us is we took over a string of condos from a non bank lender that foreclosed on the properties.