I have never seen anything that specific.  This is just one factor in determining if the ABA is a sham and I believe they only ask "Does the new company have its own office space?"  This isn't eve a "requirement", but just one of 10 or so factors that they will look at in making their determination.

However, my opinion, the more separate it actually is the better it would look to HUD.  A separate outside entrance would probably carry more weight than a leased cubicle, though either may be fine if enough other factors are met. 

Best,
Robert A. Franco
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