We went back in 2015 without a car and stayed on International Drive. Used Uber to transfer between hotel and park (though often walked to Universal). As a guide, think an Uber is about $12-$14 between Universal and Disney.
We go back first week of June and whilst we are staying onsite at Universal for the fortnight, will again use Uber for 99% of our transport.
If a group of 8 and all adults, look at signing up for an Uber account and then use the affiliate links, to link together, and you should be able get a load of free rides to start you off. We've got about 16 free $15 rides to use when we get over there.