Basenji Mix

My husband and I are the proud parents of a 2 year old Female Basenji Mix (there are some pictures of her already on here). One of our local rescues has a Boy Basenji Mix that looks exactly like our little girl, except for color! We had the two doggies meet at Petsmart and they got along great, he let her dominate, and they gave each other kisses (on the mouth!). He is a little timid around people at first, he had been abandoned at a local vet (tied to their door when they showed up one day) who found a new home for him that then sent him back to the vet (he had fought with the cat and growled at the grandpa). They think he is 1-2 years old.

He warmed up to me pretty quickly upon meeting, he started giving me kisses and all! at first he growled and nipped at my husband (who had given him space) but then warmed up to him to the point where he was resting his paws on hubbys leg and sitting next to him (he almost gave him kisses but shyed away).

He growled at an older gentleman who had got into his space (The pup tried to push him away with his paws).

My husband is concerned about aggression with strangers, not kids because the dog loved every kid that walked by at petsmart. He is also concerned about marking in the house (we have a rental, and all my husbands boy dogs growing up would mark) but the vet said they don't have any problems with him in their kennels marking, or even going inside.

We love him, but are concerned about the possible aggression and marking. Does anyone have any advice/experience with boy rescues and these things? We definitely want him, but we want to know what we are getting in to! Thank you!