How much commission should I negotiate with my buyer?

Unlike single family, the selling brokers in the apartment space are usually unwilling to split commissions.   

It deletes provisions authorizing the Commission to adopt regulations requiring the investigation of an applicant’s background.

I will be relying on his real estate experience, past experience flipping houses, and gaining a break on the selling commission.

Should I buy one of those small homes around 5-600 sqft and BRRRRI also do not have conventional financing as an option until 2020 I've been told a few times because my income is primarily based on commissions and need 2 tax returns from my current income source.TIA

Learning as I grow;)I have thought about asking my realtor to lower her commission since I would buy my next prop through her. 

Their realtor will tell them to take the offer because she wants to sell the house and get her commission.

Edina Realty, RE/MAX Results etc..) and how commissions and pay differ and what to look for.

A hurdle that is in the way, is my wife works a commission based job and she has been on medical leave without pay for the last 7 months and just return to work this week. 

I am assuming that is for the commission as the buyers agent?