The insurance requirements are inversely proportional to the premium paid. If your neighbour's insurance underwriter states 250 hours, then that's what it is unless you offer to pay for the increased premium your neighbour would incur if the minima were reduced.
I've flown a few private aircraft and in each case, had the owneer with me in the left seat. I logged PIC. I can understand the owner wanting to accompany the pilot and I found it useful as well. In each case I was flying from a strange airfield so the owner could point out local procedures and landmarks as well as any individual quirks that the aircraft may have.
Cheers
Whirls