Traveling never going to happen??? need advice

Highly doubtful as many have said. Consider that at 3000 miles round trip with a vehicle that would get 20 MPG (you're not picking these up with a Prius, are you?) you would use 150 gallons of gas. Assuming gas costs an average of $2.25 a gallon you would spend $337.50 just on gas. I can't speak for others, but 750 miles a day is about my limit, then think you will do it four days in a row, talk about a sore butt! Then there is the question of where you rest, some could sleep in the car, but let's say you get a hotel each night. For a cheapo place $50 a night is possible (if you don't mind cockroaches or unsolicited proposals for "services"), so you have another $150. So you're talking $487.50 and four lost days. Would someone do it, sure, but don't count on it. I would think $500 would ship these if you did your homework, so where's the savings? Maybe you should do the footwork on packing and shipping then build it into your asking price. That might help sell them.

Pmotz- Your thoughts mirror mine. Most people who would be interested would not be up for doing the 1500 miles in one day so you have motel and gas and in some places, highway and bridge tolls, plus wear and tear on your vehicle. I also think you've left out meals, which for 4 days is gonna cost you at least another $100. I think I'd get a quote from the UPS store or Kinkos who will insure the packing job. Split the packing cost w the buyer who then pays the shipping.

Only if they were free. And then I might ask for gas money.

Years ago I purchased a large pair of JBL 4676-A Pro Series theater horns. The bottom cabinets alone weigh 195 lbs each.
The seller offered to deliver for $500 from Ohio to E. NJ. He borrowed a friends SUV as it had a trailer hitch.
When he arrived the transmission was acting up badly.

BTW, Dkarmeli is correct, assuming you can get boxes that are the right size and you use corner protectors of some kind. Rigid foam insulation works very well,as long as the speaker is held securely in place...so that it cannot move AT ALL.