Tessio says: "I hope Mike can get us a good deal tonight."
A few moments later in front of the building the Corleone soldiers (Rocco's regime??) take him away.
Where is that? Obviously, it's not the Corleone mall. Is it Tessio's house?

Added later: The scripts say, it's the Corleone kitchen mall. I don't recognize them.

Looked like the mall to me. Logically, where else would the large group in that scene gather at that time?

Perhaps part of the confusion results from the many sets that were part of what was portrayed as the Corleone compound. That Staten Island mansion's exteriors represented the mall during Connie's wedding, when Michael came back from the hotel (and later the hospital), and when Kay tried to drop off her letter to Michael with Tom. But the interiors, I believe, were sets, and some other outdoors (like the scene you cited and when Carlo gets killed) may have been shot elsewhere than the Staten Island mansion.

It all happens at the Mall.

I would have to look again to be certain...but I believe the phone Tessio hangs up is the same one on which Sonny takes that fatefull call from Connie before being shot. It's just that Tessio is seen using it at a different angle, from the doorway outside the kitchen.

Also when they walk out of the house...sure looks like the mall to me, too!

If it is not the mall it is the mall's clone.

"Obviously, it's not the Corleone mall." What's obvious about it? Of course it's the mall. It's Vito's house. Why would Tom be at Tessio's house?

It was Willie Cicci who frisked him, so it would have been Clemenza's regime. It would be logical and symmetrical for Michael to use Clemenza who stayed loyal to bust Tessio who did not.

Cicci was Sonny's regime. Why do you think he was one of Clemenza's men at that time? Wouldn't it be dangerous to use Clemenza's men against Tessio. After all, they used to be friends.

Sonny had been dead for about 8 years when Willie Cicci frisked Tessio. Cicci was then in Clemenza's regime.

It looked pretty obvious to me that the whole scene went down in the Corleone mall.