Is it cranking and just not catching? Or not even turning over? How do you know it is getting spark? Have you pulled each plug and verified? Check the plugs themselves as well for proper gap and condition.

My first guess would be the ECU caps. Also check for boost leaks, especially around the throttle body. Look for open or missing vacuum lines too. When you buy a car for that cheap you never know what the PO did to screw it up.