brindle coloured male mixed

it's with a heavy heart I have to find a new home for him, he's 5 months old, he has 4 breeds in him. but he has alot of potential to be a working dog. due to the physical fitness not always able to take him for walks or runs, so he does need more house training. he knows the basics, sit, lie down, paw, kinda rolls half way lol, he does also know wait means.
he is kinda crate trained, but still needs work with the toilet part, doesn't mind a crate, he is a lovely boy and has been funny at times, only wish for a good loving home, and those who know about training mixed breeds.
I got him at 12 weeks, from another seller, (so I don't have his parents, but had to add for being able to post.) he's up to date with worm and flea and vax, also he's chipped so will need your details to swap ownership.
he's lovely.