Mechanic Question!

I know this may be a dumb question, but I don't know the answer... There is a truck in Maine for sale that I want to buy and drive back to NY. The truck looks pretty mint but the owner said that the #1 and #5 cylinder have low compression... My question is,

1)what does that mean?

2)How bad of a problem is that?

3)What are the possible reasons for that?

4)How Expensive is it to fix?

5)Will the truck damage if driven, and if no, how long could you drive it?

6)Most of all, how severe is the prob????

Please HELPPPPPPPP!!!!!!

I had a turbo civic that had low compression in two cylinders. It needed rings and a driver that didn't abuse it. I drove it for almost a year before blowing it up running to much boost.

1 and 5 prolly a leaky headgasket

sounds almost like a blown head gasket maybe a bent rod no telling really without taking a look inside, depends on how mechanically inclined you are i would deff. not try to tackle this yourself, over heating or to much compression could have blown the gasket, done by yourself would be price of parts or even if you have a mechanically inclined friend if not can get pricey, yes you will just be hurting the motor more, its the motor i dont know on your list but i would say thats pretty severe on mine LoL Im a heavy line tech for ford i do motors alllll day long