You can maybe get a townhome for that price but you won't find a single poolhome for $100k around Disney. That said, if you have some room in your budget, I suspect that for $175k, you could probably get a 4 bed fully furnished home with a pool within 15 minutes of Disney.
I haven't purchased but I suspect you can get a fair amount below asking but I just don't see you getting 50% below asking (asking price for 4bed pool home is probably close to $200k). In case you haven't done any research, as a Canadian buyer, financing is likely the biggest hurdle. You likely *can* get a mortgage from a US bank but you'll probably need 40% down (or more) so you are looking at roughly $100k CND down.
Personally, with all the available properties, I would not recommend buying a new home (I suspect that for the price of a new home, you can get a resale that bigger, closer and fully furnished).