Double Bicycle Trailer/Stroller

Yes you need to check your bike to make sure the trailer will attach. Not sure exactly what you have so I'd take a picture of your back wheel and Email it to the manufacturer to ask.
This is crazy I know but I have owned a bunch of them (all purchased at yard sales for $50 -$100) I kept 'upgrading' because I thought with more room or a more comfortable seat design or bigger window the kids would like it more. One did the other always hated it. So before you spend a lot of money I would ask friends if you can borrow theirs and try it for a couple of days.
In hindsight I wish I had just spent the money and bought a 'Chariot'. It can be used as your everyday stroller and a bike attachment. It's three times the price but saves space and it's the best design just in my opinion (windows, how the seat hangs, wind and rain proof, separate storage compartment, sturdy floor).
Also where I live they are very popular so you can get at least 50% of your money back on resale. Even if you buy one and beat it up with use you can resell it to people who use it for a dog carrier!
As well as comfort for the kids so they will like it and be safe; think about the width so you are less paranoid that someone will clip it as they ride past.
Look for a brand that has a pin to secure the carrier to the bike rather than just screwing it to the wheel which can come loose AND a 2nd safety strap to between the carrier and the bike so if one fails you have a backup. I liked the Burley's design for connecting to the bike best. The Dreamcatcher design was the worst. But the kids liked the Burley the least. My friend has the new Trek model and loves it.

Don't worry - sounds complicated but it's no where near as complicated as buying a stroller!

With our trailer, all bikes worked because of the way it attached, but my husbands bike needed an additional rubber thing on it (we made from old bike tires) to keep the clamp secure and keep paint from chipping. My bike didn't.

Just be sure that when you are looking at the bike you want to buy you take into consideration the trailer and how it attaches, etc.

FUN! I loved our bike trailer and used it until my oldest was almost 6. then they got too heavy:)

I'm actually selling one right now on Craigslist! It is in excellent condition and it came with everything we needed to attach it to a bike. We actually used it on more than one bike. You can message me if you'd like me to send you the link to my posting.

The bike trailer will be made with an attachment for just about all bikes. It's basically a claw-clamp that screws down and grabs one of the bike's metal frame pieces near the rear wheel. Then there should be a safety strap that loops around the frame too. Bikes themselves don't have trailer hitches.