Well usually, you can find a complete head, with the intake mani, dizzy, VTEC solenoid, ect for about $200... That only leaves out the ECU, which can be found for about $100-$120... Versus the cost of a VTEC controller, which go for about $200+ for a decent one (Apexi) that handles A/F and VTEC... Then on top of that, u have to get it tuned by a professional... Anyone can tune it to do VTEC at X amount of RPMs, but you also need to find the right amount of A/F to add to the mixture, otherwise you might as well just throw on an RPM activated switch and call it a day... Which will def hurt performance...

Now thats $100 less to just buy the ECU and do it right, but the only thing is the wiring... You can do it yourself, and save that $100 you saved, or you can get an OBD0 to OBD1 harness for about $100, so that puts you about even with the VTEC controller (not including the tuning youd need with the controller), and its done the way Honda intended...