Even with Curtis Cab doors on sale for $2500, you really only need them for two months of the year. The rest of the time they're adding weight and once in awhile keep you out of the rain while you sweat.
The other option is to buy a cart with doors already. Before I did that, I would think outside the box. Air Conditioning and heat and a radio would be nice. This can yours brand new for $11,000, that's $4,000 cheaper than the other alternative, the Atomic Cars. The Crown View II sold right here in Wildwood behind Russell Candy, they advertise in the Daily Sun all the time.
Crown View II | Crown Golf Carts