My two beagles, Fred and Edward, are the most spoiled dogs you could ever meet. Old Fred is about 10 so I worry about him too, especially since he's struggled with yeast infections in his ear since he was just a pup. It used to be that he would get out and explore every chance he got, but these days he's just too old and uninterested to even try to get out the door.
Edward on the other hand is a total snot. Beagles aren't stupid dogs like you may think that they are and once when we first got him he figured out how to climb on the porch swing and jump over the fence on the patio. That was scary. We searched everywhere for him for at least an hour and a half, only to come back home and find him trotting back to the house. I wouldn't be so scared for them getting out if we didn't live by the highway. I know they would come back, but because of the highway I know that there's a big chance that they wouldn't...
We had these horrible neighbors who lived behind us and they hated our dogs, so before they moved away they opened the gates and let them go! D: They better be thanking their lucky stars that nothing happened to my boys because my normally reserved self probably would have lashed right out. They could have been killed, but thankfully we found them taking their walking route trying to get home. Talk about a HUGE sigh of relief.