I'd like an expert diagnosis before tearing apart the engine.
Going back from the start:
I purchased the car as is.... not running.
According to PO car was running fine, and on the way home it stalled. Engine stopped. Would not start.
Now by "not starting" I dont know if the PO meant it was turning over or if it was cranking but not starting.
When I got the car the battery was dead.
Battery was replaced and I tried to start it, but it would just turn over like an engine with no compression.
I found the Alternator serpentine belt was missing. (Quick fix I thought!)
I installed one. Engine would crank, but not start.
Then:
I checked the timing belt to see if it broke or for signs of slipping or broken teeth. All there, belt is good. Belt is not new, But its all there, intact.
I checked the timing. Cyl @1 at TDC, both camshaft marks aligned and crankshaft also at its mark. Timing is correct.
I checked for compression on all c 5 cylinders. All read 0 psi. Tested the compression tester on another engine. Compression tester is good.

Now, I'm no master mechanic, but I pretty much can figure engines out (I think).
I find it hard to believe that all cylinder would have "0" compression due to bad rings or bent valves.
It's like if the valves aren't opening and closing at all. Could it have to do with the VVT? I know nothing on how that works. (I plan on reading something on the topic).

Any suggestions? before I tear it apart.
Thanks

 

What kind of car?

 

My guess is the belt shredded and got caught in the timing belt. Previous owner tried to reset the timing and it didn't work so they sold it because it needs valves.

Do a cylinder leakage test to see where the compression is going. Or get an inspection camera to look at the valves. Or pull the injector rail or intake to look at the intake valves.