I am having 2 distinct intermittent starting problems with my car, hope someone can help:

My battery has been load-tested and is fine. The mass air flow sensor was cleaned recently with alcohol on a Qtip. The OBD reader is not returning any code. The car has 50k miles, was serviced at the dealer a few months ago, nothing reported. The spark plugs were routinely replaced at the time.

1/- No sound at all when key is turned to starting position. Happens with engine cold or hot. Putting the shift lever in Park or Neutral position has no effect. The engine will always crank and start after a few tries, just like magic. Runs fine once started. From my readings of the posts on this site, I suspect the starter relay may be defective. Am I on the right track? if yes, can somebody post a picture or show me where to find this relay? Anything else could cause this problem?

2/- Engine cranks strongly, but will not start. Happens with engine cold or hot (all accessories being turned off, I can hear a faint sound with key on position 2). When this happens, depressing the gas pedal fully will get the engine started every time. Runs fine once started. Fuel economy is good. Again, from my readings, I suspect a defective fuel pressure regulator. Am I on the right track? If yes, can somebody tell me where to find this pressure regulator and how to test it? Anything else could cause this problem?

Thanks in advance