Minimum Launch Cost

What do you think the minimum launch cost would be to orbit? I'm
interested in what factors may apply: launch fees, basic insurance,
bribes, whatever.

For the purposes of answering this, I have a 200 gram Estes rocket
fueled by unobtainium. As we all know, unobtainium is free and allows
SSTO in 200 gram Estes rockets! So the only costs would be launch
fees.

The reason I ask is, of course, the recent papers on the $1,000 per
pound launch minimums. They state that insurance costs and range
launch fees would set that minimum. Can you legally avoid the launch
range fees, for example by building a very small rocket and building
your own very small launch range (a la Sea Launch)? Do the per flight
insurance rates scale with rocket size, launch location (the middle of
the ocean, say), flight rate, or anything else?

Thanks!

-David