Hi A-D!
I just happened to stumble on your report in the Orlando off site section (I was looking for something to do at night outside of the parks).
Sounds like you have a lot of planning to do and budgetting! My first thought was a rental condo would be good for you and your Mom for the month as they are generally cheaper and you can cook some of your own meals. Just remember to add the parking fee for the parks in when you figure out your comparsions if you will not be staying on site.
I've seen good ticket deals for multiple days at US/IOA. Go to their website and sign up for their emails.
You have to go to Sea World....I love it there! And it really could take 2 days to see all the shows.
I haven't been to NASA in 20 years so I understand why your Mom might not want to go but from what I have seen and read it is much bigger and better now.
Good to see you back on the DIS!