Squonk costs podumes. The exact calculation being a second order derivation of the number of podumes a player possesses, the LV they actually possessed at the time they declared squonk and the quadrant they are in. The governing formula is:
As an example of this calculation, if you have LV of over 14 in quadrant two with podume levels above 8 and below 13 and declare squonk you can remain at your current position inside quadrant two for three moves but lose 8.7 podumes. Obviously you can't lose 0.7 of a podume so the true value is nine podumes.
If you don't have enough podumes to pay you can run a negative balance for two moves but should you remain with an overdraft you will be placed in strick.
It is very important to note however that squonking is risky as it can lead to an unpleasant inversion i.e. LV increasing to unmanageable levels. LV at ~99% of the speed of light is theoretically possible if a little unlikely.