To drill the many holes required for grab irons and such items, I purchased the Skil battery-powered drill that you see in the photos. There are many of these on the market, but a couple of key features that I required were, it had to be of this shape, it had to be battery-powered (rechargable), it had to have a 1/4" socket (most have metric ones, which require a conversion bit, which is a pain), and it had to be lockable (many use magnetic force to hold the bit in place, but that is too weak).
(external link: Skill Screwdriver)
The added bonus of this particular model is that, when the unit is not engaged, the bit is locked, so that you can use it as a regular screwdriver/drill. The way it works is that the large, knurled ring is moved to the right to make it drill forward, or the left to drill in reverse. The model has two LEDs that turn on automatically when the unit is engaged, and stay on for a few seconds when you disengage it. It took a bit of practice, but eventually I learned to control the unit using just my thumb, which works well. In general, I am very happy with this unit, and it has definitely sped up the chore of drilling many holes in models.
So, while the model above is labeled as a screwdriver, I use it for both a screwdriver and a drill. This photo shows how the drill bit chuck nicely locks into the drill, and away we go! The drill's grip is solid. All of the odd shapes on the handle area help in eliminating the thing rotating in your hand. While the overall shape of the model is round, it will not roll off of your workbench. It will move a little bit, but there are enough "things" in the handle that keep it from rolling indefinitely when you put it down.
I bought this unit when I started needing to drill holes into the Pre-Size Model Specialties Southern Pacific 50-foot box car that I have documented elsewhere on this web site, which has well over 120 holes to drill on it. Not only did that speed things up, the initial charge I put on the unit is still holding strong. We'll have to see how long its charge will hold before needing a recharge. The documentation does not show anything about being able to replace the battery, so at some point in the future, the battery will not be able to hold a charge for too long and will need to be replaced. It appears that there is no way to remove it, so a whole new screwdriver/drill will need to be purchased at that point in time (hopefully many years down the road). The model comes with a charging cable that plugs into a USB port of your computer, but nothing with which to charge it from a wall socket.