On the budget side (say $50-75 range)- Extended Stay America Westwood blvd (there are 2 to choose from one used to be ES Deluxe)- they are about a 10 minute walk to the entrance of Seaworld cutting through the street that runs from Westwood blvd to the Seaworld team members parking lot. Super convenient location. I stayed there for many months when moving to Orlando and would recommend it - it is budget friendly and clean - great staff.
On the more deluxe side ($100) the Doubletree is a bit up and across from Extended Stay America - very convenient to Seaworld. I have heard of people booking it through hotwire for a good rate ($60) (check betterbiding.com for more info on bidding for hotels through hotwire). But I think they do have a resort fee.
After that I might look into Marriott brands (both a Fairfield Inn and Springhill Suites nearby - and Renaissance), other Hilton properties (Hilton Garden Inn or Grand Vacations). But these are usually ($100 plus).