Appropriate Length for a Walk

I've never had a dog that really needed a very long walk (mostly toy breeds, never big labs or dogs that needed hours of exercise), but I'm nervous with my new basset hound, Whiskey.

She's doing really well on the leash so far, and I take her out many times a day down stairs (I carry her down the stairs because I read about hip dysplasia) and then we walk around the building to the area at our apartment complex that's set aside for dogs to use the bathroom.

It took me years to get our pug on a decent walking schedule, adjusting the length of the walk as we went, but I really want to start Whiskey off on the right path. But because of the joint problems and hip problems I've read about, I don't know what is considered an appropriate length of time to walk (and how many times per day).

Is a long walk going to help or hinder future joint and hip issues?