I strongly suggest that anyone who may possibly need an ECV, rent one from off-site ahead of time. The parks will definitely run out, and early in the day. Even off-site places will sell out.
Remember, there is a difference between surviving Disney and really enjoying it. There is no reason for your husband to push himself and be so tired when he can use an ECV and have more energy for the things that really matter.
If there is something OTHER than fatigue/stamina that will affect your husband and dad, then definitely ask about a DAS for them. But even with that, an ECV will help a ton. There is still a lot of standing, even with the DAS - fireworks, parades, restaurants, buses/trains/boats, anything outside the parks, and the lines after you return (FP entrance usually).
Hope you have a great trip.
Remember, there is a difference between surviving Disney and really enjoying it. There is no reason for your husband to push himself and be so tired when he can use an ECV and have more energy for the things that really matter.
If there is something OTHER than fatigue/stamina that will affect your husband and dad, then definitely ask about a DAS for them. But even with that, an ECV will help a ton. There is still a lot of standing, even with the DAS - fireworks, parades, restaurants, buses/trains/boats, anything outside the parks, and the lines after you return (FP entrance usually).
Hope you have a great trip.