Happily, in most cases the answer is usually yes. The bottom line is that there is such a variety in accommodations that something is available to fit just about every budget. From campgrounds, to hotels and motels, to upscale resorts, to luxury vacation homes - Orlando has it all.
Before I begin, there are 4 main components to how much a Disney trip costs. First, there is the travel, second, the accommodations, third the food, and fourth the DisneyWorld tickets. Everything else is fluff.
Travel is pretty straightforward. Finding cheap flights to Orlando is easy with sites like Expedia, Priceline, etc. One thing that many people forget about when planning their vacation is the cost of a rental car. Of course, if you are staying at one of the Disney Resorts - then the best option is to take advantage of the Magical Express Bus service - in which case you won't have to worry about this cost.
The accomodations piece is where you have the most flexibility in making Disney vacations affordable . In a nutshell, they can either be very cheap or very expensive. Also, the length of the trip matters here. A one week trip could cost less than a two week jaunt - but not always. Often for longer trips, families will seek out rooms or suites that have kitchenettes and laundry facilities. While several of the hotels on property are set up for longer stays - you may find a better deal by staying in the surrounding areas. Keep in mind that many tourists think of central Florida as Orlando. In reality downtown is actually quite far from the Disneyworld theme parks. Obviously staying on property will give you the shortest commute - however, the surrounding areas of Kissimmee and Lake Buena Vista are pretty darn close as well.
Food is another big cost center. If you are a Disney resort guest then you have the option to purchase the Disney Meal Plan deal. Again, individual appetites need to be considered. My family is always hungry - so this worked out well for us and I found the cost to be reasonable compared to what I would have spent off the plan. Also, eating outside the parks will be cheaper - but how often will you be in your hotel at mealtimes. Take your touring plans into consideration as well.
Finally, the cost of Disney tickets needs to be factored in. This is one area in which there is not a lot of flexibility. Any which way you look at it - these are expensive. Now that the Mouse has implemented the Magic Your Way passes - at least you can customize the features that you need. But each additional day is considerably less than the day before - if that makes sense.
So you tell me are Disney Vacations affordable or not? The way I gauge the price is by figuring out how much an alternative would cost - say a beach resort vacation. Then I compare this to my theme park plans and figure out the difference. Now I can easily choose how much I want to spend and where I want to go.