(wife - "women have lots of hair products and stuff that they like to use.

As far as how much to charge, negotiate based on a reasonable rate for your area, and maybe go just a hair lower than normal to earn the initial business.

i am looking to purchase a 4 unit apartment with a very nice, furnished commercial space that is currently a hair salon with all of the equipment.

@John Matthews I went through this exercise about 3 years ago while trying to manage some of the same issues you mentioned - #3 in particular, and also because at least one of our properties didn't fit into a nice Fannie Mae box (urban residential use, but think of a tenant running a small hair styling business).  

.$3500/mo rent Rental Home 1 - $65k value Rent - $800Rental Home 2 - $65k value Rent - $850Rental Home 3 - $65k Value Rent - $950Rental Home 4 - $65k Value Rent - $950Rental Home 5 - $65k Value Rent - $50027,000 sq ft lot - $150k Value Rent - $800(small used car lot)37,000 sq ft lot - $150k Value Rent- $400(small 400 sq ft hair salon)10,000 sq ft lot - $300k ValueI have a good bit of cash every month coming in from these rentals I've amassed and Im making good money at work and I have a good property manager, would it be better to 1) pay down my home and save the money im paying monthly2) pay down the expensive rental which is my retirement property on the beach one day but leased out now 3) Just stay the course and keep adding rentals and using income to pay down the 2 properties?

@Rob Barry I'd say that 10-caps are extremely rare in this market and if you find one, there are either one of two things going on:  the seller has left some major expense component out of the pro forma they're showing you; or the deal has a tremendous amount of hair on it.  

My question is I put rent a hair under fair market value, now that I know I have this many applicants what I wanted to know from all of you seasoned managers is would it be unethical to put a spot on the application for a "Highest rent willing to pay for listed property" and see if I get some higher bidders to give themselves an edge in the application process?

@Doug Bryant Doug, flips typically come with more headaches and hair than rentals IMO -  so most people from the start slowly get into the industry. 

Whats it to them if you have $50,000 off the property, or light a match to it once its out of their hair?!....

I am a Senior Manager at a regional accounting firm in the area and my wife is a self-employed hair stylist.As for real-estate experience, we have none with flips or rentals.