First, you don't really need a piece of equipment (treadmill, stationary bike, elliptical, etc). You just need to go outside and move: walk, jog, run, whatever. But perhaps going outside isn't an option (for whatever the reason) and you are determined to make a purchase.
First (as always) check with your doctor before starting exercise. You aren't as young as you used to be, and your doctor will have some good and effective ideas for you to try. For example, my doctor told me to use an elliptical because it would be easier on my joints.
Next, whatever piece of equipment you get, make sure it has plenty of handles and bars. Most people give up on using the equipment and use it, instead, to hang and dry clothes. You want to make sure there are a lot of places to hang things.
And that brings me to my third piece of advice: don't buy new. It is very tempting to go to the store and pay a lot for something shinny and new. Don't do it. Look at the classified or craig's list and you will find a lot of equipment for sale. Most people buy the equipment and then don't use it. And many of those people will get rid of it instead of hang clothes on it. Often these pieces of equipment have only been used a couple of times! And you will pay pennies on the dollar!
I have a fully stocked gym in the basement of my house - nearly all of which stocked, pennies on the dollar, with slightly used gym equipment!
Different equipment will have different bells and whistles and stuff: digital displays, coaches, phone connection, disco lights, etc. Just set yours up in sight of a TV with a fan to blow on you and the bells and whistles won't matter. Sure the bells and whistles are fun.. the first several times you use it. Then you'll realize none of them really matters.
If you are getting a treadmill or elliptical, three things do matter: (1) The length of the track. If you are tall, you will need a long track. (2) The weight limit. They always over estimate the weight limit so if the limit is 275 pounds? You better be under 250 or the machine is going to break. (3) The incline. You want to be able to simulate walking up a slight hill. It doesn't have to be a crazy 30% incline, but you will want some kind of an incline (10% is often fine) to continually challenge yourself as your body adapts to the exercise.
You want to try it before you buy it. When you try it, listen for sounds such as rattles and squeaks. The sounds might not show up until after the machine warms up a little. Small squeaks become big squeaks and will drive you (and everyone in your house) nuts. You also want to feel for nice fluid motion. Even a small bump or jolt will lead to joint pain over prolonged use. If you are handy, you can usually order the parts and repair the equipment yourself. If you aren't handy - stay away from equipment that is demonstrating problems.
When you get the equipment home, you want to place it on a rubber mat even if using the equipment on carpet. It can be a thin rubber mat or those foam floor puzzle pieces - it doesn't matter. The mat will protect your floor, will protect the equipment, and will protect you while in use.
If you decided to go with used equipment, you might not know how long the equipment sat unused. Most equipment is lubricated with a long lasting silicon lubricant. However, time, dust, and lack of use can cause the silicon to become ineffective. You should give all the moving parts a once-over with a high temperature silicon lubricant.
There you have it! My advice on obtaining home exercise equipment. Let me know how it goes, and, good luck!
