Simplified 7age swap?, I just need some help Options

[MtownRice]

Hi, im new to all this. Bought my celica not expecting to want to modify but that changed a week into owning it haha..

I have a goal for 400-500 whp but im pretty sure i cant get that on the stock 7afe.
I cant really do a 3sgte swap unless i hit the lottery or somehow come across the money because the 5k i read it would cost would take me forever to save and be able to do it.

I found a 4age head on google for around 300 bucks and have been curious about the swap. Im new to this car stuff and when i try to research it the discouragement takes over pretty quick.

So i know it has been discussed but i cant really find the steps involved. If someone would please help me with information i would be grateful.

Or atleast give me a different start to my 500hp goal. I thank you in advance.