Kijev

Kiev was mentioned in one relation as Sambat. I have read that Kijev's name should be related to Kuji- root. Let us speculate that names Kiev and Sambat mean the same.  Can you find explanation in iranian languages say:

Hujjat and bat. Maybe sam,- is slavic siem,= clan, family, tribe.

Similar construction we can recognize in the name Grumbates (the king of the Chionites) where Grum seems to be slavic Grom (lighting, thunderbolt) than bat should be identical with slavonic suffics slav = glory. Therefore Grumbates would be identical with polish name Gromoslav. Going this way one could conclude that Avars name Batbayan in. iranic would be identical with later Czech and Polish royal name Boleslav.

To some extent, yes. Kiev (in polish we name it Kij�w, sounds like kiioof) was the homeland of Polanie (Polans). Later they moved west and dwelled in so called Great Poland. However sources don't say the exact area of their settlement. Perhaps Kuiavians are the same people called Polanie. In russian Polanie could be translated as Steppe People.

And the Slavis homelands were slightly West of Kiev, too. 

Day I, sometimes it is good to provide some material supporting your ideas   I am not against this theory but Khazars came to those lands much much later then Kiev was established according to archeological data.

Actually I thought that Khazars were bit south-east in the east part of Black See.