I have towed our 944 for the past 5 seasons using a Vintage/Millineum 24 ft., regular construction. 20 ft would be big enough, but very limiting in extra space for say a scooter, or extra wheels, cabinet or shelf. Aluminum is very nice and will hold it's value if taken care of, but initial cost is considerably higher. Get the extended frame/tongue, it will keep you out of trouble when backing up. Overall weight may be a consideration as well. We tow quite a bit of equipment, wheels, tires and tools, with our gasser with no problem though. Yes, a winch is helpful, but in reality, I use mine little. I have a big tire rack down the upper right side of my trailer, but still, with a little practice and maybe even an assistant up front, you can drive it in, There is plenty of room to squeeze out of the door. Low clearance is not an issue except on the front lower nose. A stock Boxster should be fine most of the time, as most trailers are beavertail in the rear. However, sometimes depending on the lay of the ground or the angle of the parked trailer, you may have to place boards in front of the front wheels when going on or off the ramp to prevent nose drag, but my car is very low, and I have had minimal problems. Also, in a pinch, if you have no boards, you can raise the front of the trailer (while hooked up) a little to change the angle. We tie down using axle straps through the wheels, avoiding the valves. Cross front tie down straps in an "X", and rear tie downs straight away. Leave car out of gear once tied down, but remember this when you release the straps!
Carl and Valarie * 1997 National RV Dolphin 535,
2003 Jeep Wrangler, 944 Porsche NASA-GTS/2,
Yamaha Roadstar Silverado/Yamaha CT175/Honda Spree, 24ft Vintage Trailer