If not, I would put down 6 mil vapor barrier, run nailers as John suggested, and install foam panels between nailers so entire floor is supported.

If your policy is each unit can have one pet (under 25 lbs.) with no pet deposit/rent (or whatever it is), you can't suddenly have a different policy for your tenant's cat to try and skirt around the fact that her b/f's service animal will be moving in. 

Some good measuring advice here... and what worked on my fourplex was a really good vapor barrier (over a bare earth floor) with no gaps, even up against wall.

In my area they usually lay the vapor barrier on the ground and insulate the walls with foam, without venting.

Oddly enough the "money" was gone in a flash, but it took the bean-counters YEARS to recognize the theft (while the favored few enjoyed their playground without a clue).Of course when your accountant's name is MOSES, your *** is gonna be dragged at least 40 miles through some tough territory...http://www.newwest.net/topic/article/yellowstone_club_how_to_go_broke_on_375_million/C35/L35/Just another story of money returning to the vapor it was, nothing serious, a few might get slapped, but NOBODY IS GOING TO RECOVER VAPOR PAPER here or elsewhere.

Sheila is doing all she can with the game she was put into The Multiple of vapor paper to real money is under 35:1, it needs to go to 20:1 for this to work again.

It went from "Vapor to Paper", now it goes back to Vapor.Enjoy the show......

You just take your earnest money and contract to a title company and they take care of it for you.On a side note, I just wanted to thank Herb for drudging out this thread.

. $200K can vaporize quickly in a deal like this, resulting in a loser.A better calculation is to take the ARV, subtract 20%, then subtract the cost of rehab plus a contingency, and the total purchase price paid by the investor, including your fee, shouldn't exceed that amount if they are to expect a successful outcome.

A water, moisture/vapor, air barrier is better to be in place, such as some kind of flashing, elastomeric products, or similar.