I am coming up to Worcester this weekend! Small world.
You have several options. But many are determined by the condition and type of stair that you have uncovered.
If they are built on site builders stairs with square fronts on the steps, you can cover them with a laminate system to make them look like real hardwoods. They sell bull nose trims for stairs and its just a matter of gluing and nailing the wood over the existing steps. Remember though the step will be a bit higher once done all the way up. Meaning the top step will sit proud of the upper level floor.
If the wood looks ok, but not really good enough to stain, you can paint them. With all the paint systems you can end up with stairs that look like expensive hardwoods and not just plan old white.
Or if the wood is in really good shape and they are not just pine you can sand and stain them to look nice.
The last method is to paint the sides and the steps and risers, Then install a waterfall type carpet down the middle leaving the exposed edges. This tends to be the easiest and most long lasting as well as safest thing to do. The carpet hides the bulk of the riser and step leaving on the four or five inches of exposed step and riser left. This reduces the amount of work you need to do to paint or stain. The carpet helps prevent slipping on a painted or stained wood step. And lastly the carpet will last much longer then paint on a stairway. Painting oftentimes results in wear much faster then one would like on a stair case.
Thanks so much for the help. I'm leaning toward the sand and stain option. The wood is in reasonable shape. I was told about a stain polyurethane mix. Any thoughts on that? Also, there are a couple steps where a small piece of wood broke off (on the planks under the step itself). Do you know what the best way is to fill in those spots?
Brian, the stain poly mix readily available is called Minwax Polyshades. This will help camoflage some imperfections however it is not dark enough in itself to give a nice stained look.
First, sand the wood to clean it up and smooth it out. Then apply a coat of normal oil base wood stain. After an overnight dry, brush on two coats (so you don't sand through the stain) of clear poly and sand it smooth. Then you are ready for the polyshades followed by two more coats of clear poly.
Polyshades is a little tricky to work with because you are simulating the wood grain with your brush strokes. This means every stroke must line up with the grain you are going over. Oh, and better be quick because it sets up fairly quickly so you can't go back and touch up, it's unforgiving if you do.
This will give you a rich furniture type finish that will last for years.
Thanks for the help guys. I ended up going with the stain option. The stairs were in reasonable condition, so I sanded them down and put some stain on. Because it's a rented house and I wasn't looking for a long-term solution, i went for the Minwax. They look quite nice with one coat. I may put on another coat just to make sure it lasts longer.
I would opt for at least one more coat of stain. Not a lot more of work and the results as you already understand will last longer. Might as well as you already have the stuff on hand to put it on.