Why is My Car Not Starting on Occasion?

Bought a used 92 Lincoln Town Car…real nice car with low miles. I have had the car about three months and have had to jump several times. First, I had tire kingdom replace battery terminals, still problem starting the same day.. noticed they were loose and that seemed to be problem. They actually told me car had dead or weak spot in starter when I brought it back though and wanted $350 plus to do work. I had them tighten cables and drove car home. I had a few more occurences of being unable to start and brought to a different tire kingdom again..this time they said battery, starter and alternator were fine but I was skeptical. They thought I had left a light on or door open. I was almost sure I had not left any lights on or doors open. Then, I noticed the radio which had died on me had a short and was not turning radio off properly..not sure if radio died before terminals were replaced or not.Anyways, So, I made sure that car antenna went down before turning off car and that helped… the power button still made antenna go up and down even no lights or sound from radio.problem persisted… The guy that sold me the car said he replaced battery so original I ruled the battery out as causing the problem. Battery had a two year old date though and looked cheap but still kind of new..decided to replace that…now I am still having same problem.. note: on all but one occasion, the car jump started, one the occasion it did not jump start, it, started right after trying to jump…my newest theory is I think that I have been driving the car on real low gas the times it does not start up but not sure. I know that on the last two occasions, car was very low on gas. I never had a digital gas gauge and have over trusted it on a 92 car. Some guy hooked up battery cables from his battery to my solenoid and said it didn't spark so solenoid is bad? My main question is why would the car jump start if car is low on gas???? Also, if starter or solenoid were bad, would car jump star

Solenoid. When it is troublesome, the car won't start one minute or hour, but will start later sometime. You can replace it. Or you can tell yourself that the good Lord wants you here for some reason and the car will start when that purpose is accomplished. Of course, if you have run out of gas, He might not let it start later either.