I own a Greyhound dog and volunteer with a Greyhound adoption programme for retired race dogs. I find it really hard to understand why dog sites always promote this breed as requiring lots of daily excercise. This is just not the case.
They are a short distance dog, yes! However, they are happy with as little or as much excercise as you wish to give them. The majority only require a 15 - 20 minute walk every 2 to 3 days. If you want them to walk more you would need to work them up to it and extend their time, length and frequency till they are able to cope.
They are the perfect pet for busy homes and more often than not are quite happy whilst busy owners are at work choosing to quietly sleep.
Please don't advertise this breed as need lots of excercise on a daily basis. Many people would read this and discount them as a family pet when actually they would be ideal.