I am also concerned that it will hold up sale of the property.

It's a Plus for your tenants.. would I want to lug laundry down the block or down to the basement.. your tenants will stay longer, and you'll rent the units out quicker. overall original start up on anything is a cost consideration.. call around for quotes on lease options.. ask if they have used machines for sale ... check craigslist for used machines. 

Their are a lot of homes for sale in those neighborhoods that do not have signs out.

I asked your questions to my mentors who've been through multiple cycles and they told me that they don't try to time the cycle, they knew from the start they were holding for the long term.

All three properties were acquired through a previous tax sale by the current owner who is looking to sell them to me.  

Should I ask for all of that off the sale price?

with permission of the homeowner most water companies will give you the monthly reports for over a year I recently made a sale and the new owner asked for this info I was able to download the information for him with monthly usage,great graphs, and of course billing i could have went back over 3 years 

Specifically new home building and sales.

The bank won't reduce what is owed unless if it's a short sale.

Younger families are starting to move into town so single family homes might be a little more advantageous since it would seem there's not much of a seasonal cycle due to fall and spring semesters.