2013 Buick Verrano needs work - $1,500 (White Lake)

$1500 OBO.
170k miles.
Car being sold as is and will need some work done.
In March I had $2500 worth of work done on the car including the full timing chain kit.
Now the car started to make a noise in the engine and I had it looked at by a few people.
I’ve been told it could possibly just need a full tune up with new spark plugs and was also told it would need a new engine.
Car still runs but I was told not to drive it any more as it may cause damage.
Car recently has 2 brand new tires and new brakes put on.
Recent oil change.
$1500 OBO as is.