2003 Nissan - Sentra GXE - Spark plug if gets broken.

Since last few days I started experiencing problem with my car, as it started giving jerks while started or accelerated.

I was told Spark plugs need to be replaced. Mechanic told out of 4 only 1 can be taken out easily. Rest 3 are hard to be taken out. He mentioned, he needs my approval - As while taking the hard one's out these spark plug might get broken & half will stay inside. To rectify this damage he mentioned there is a high cost around $1600 to $2000.
If all 4 comes out smoothly then there will be cost of spark plugs only.

Isnt there any possibility to take out the tight fitted spark plug without loss, & what could be the cost for these to take out?

As well those Jerks I experience, is it really due to spark plugs?

Thanks & regards.