If you want to have my word too this then i only say the following again:
No word about TC4 and a release date or a possible/further delay as always
So TC4 will drop when it´s done(tm)
Atm the only "sign of a release of TC4" is the global Cryo Booster of the current Spaceball event as it would make sense to "shower the players with cryo to be prepared for the new armor and tech that needs to be installed and will cost a fortune".
I personally expect for Parsec/RDX ships alone 1 million for the next armor while ne0n´s should be around 400-450k eventually and the items could cost at least 200k minimum so you can expect at least 1.6 million here and with rares make it double again to 3.2 million.
jup the next armor could be around 1-1.2 mil. and the rare techs should tend from 450-700k.
the worst thing is the ne0n ships could cost 1.3-1.7 mil.
but we will already spend more cryo in the first techs and best blue techs. upgrading the existing ships will be more expensiv than build the r99 parsec or rdx ship directly with rare tech. i remember how i upgraded my parsec storm with mixed sirius and kenyte techs, later perceptron techs, first tc armor and modal logic techs and then calon deep recurrent techs
also my sirius paragneiss did get the same experience but it was Upgraded with moda techs and tc armor and 6 Months later after tc3 he did get the deep recurrent techs as well. hard decided to do that. so yeah, my parsec storm was the most expensive ship that i ever build