The actual cost of replacing concrete steps is inevitably dependent on a range of factors, such as where you live, how many steps you want replaced and the size of those steps, as well as whether or not you are replacing the steps yourself or else hiring a contractor or builder to do the work on your behalf. Since the size of the job affects both the amount of materials needed, and the time it will take for a workman to do it, its quite difficult to answer the question without precise proportions. However, assuming that you live in America, you ought to be able to buy a bag of cement at a fairly cheap price from a couple of dollars up to maybe ten dollars depending on the exact size of the bag, with the cost of the concrete for say one step of proportions 6 inches by 36 inches by 36 inches, being no more than fifteen to twenty dollars in total. Concrete can be bought by the bag load from any retail shop, for example Menards if you live in America, or B and Q if you are in the United Kingdom. If you are considering doing the job yourself, then you will also need to buy some other materials, and whilst these don't have to be exact the following list will give you an idea (assuming you are repairing one step of the above size): Ready made concrete mix as already explained (or alternatively, portland cement, water sand and aggregate to make the cement yourself), a wheelbarrow, a cement mixer, a shovel, a trowel, form lumber, sixteen penny duplex nails, a hammer, and a screed board. If you are doing it yourself then there are plenty of Do It Yourself advice websites online, this one for instance deals with making a step for the size step previously mentioned answers.yahoo.com/question/index?qid=20071126170818AAPsItc, or this site offers more general advice: www.doityourself.com/stry/how-to-make-steps-with-concrete . If you are unsure of how to repair the concrete steps then you can also find websites which offer video tutorials on the subject as on www.youtube.com/watch?v=gpdMrbRHBLU If you do it yourself, then judging by the materials needed for a step the size we have been discussing, it ought to cost you in excess of no more than fifty dollars per step, as well as taking a minimum of three to four hours. However, if instead you wish to hire a contractor to do it for you, then the cost of their labour (plus the same materials) will be significantly higher. A decent contractor doing a good job will probably charge you at least a couple of hundred dollars, and possibly a lot more - though this is dependent of course upon whom you hire. Their pay will be decided on the number of hours the job takes them, and so the final cost will be decided by how efficiently they work, and how much they charge you for the materials, assuming that you haven't provided your own.