On a $70 fare long distance like that (well, reasonable distance), with dogs and bags, I'd almost be inclined to bite the bullet and give the driver $100 total. That's still a bargain for that trip all things considered. If times are tough for you, then $85 - $90 total is probably appropriate... but given it's a limo, my guess is that the $30 tip will be well appreciated by the driver... you might find your return trip (if required) to be a bit more special - e.g. you might even be able to negotiate a free ride up and down the strip etc....
If there are a number of you travelling, this is even more of a bargain. E.g. 4 people in the limo = only $25 each. Cheap.
If there are a number of you travelling, this is even more of a bargain. E.g. 4 people in the limo = only $25 each. Cheap.