What size wheels

[Ferdinand]

I have a 2004 Club Car DS. With a 3" lift kit added,can I safely add 12" wheels with low profile tires or must I go with 10" wheels?

[dougmcp]

The size of the wheels is really not as important as the diameter of the tires.
A stock golf cart 8" wheel and tire is 18" in diameter.
10" wheels with a 205/50-10 tire is 18.5" diameter and a 12" wheel with a 205/35-12 tire is 18.5" diameter as well.
The difference with these, other than appearance is the ride quality, the lower the sidewall of the tires, the rougher the ride.
Lifts generally require the use of an offset wheel or spacers.
I think with a 3" lift you can go to a tire as large as 22" diameter before you have possible issues.