If I have an item listed on ebay with a reserve and no buy it now price or best offer can I end auction early if someone offers me a price more than the reserve to buy it now or does this break ebay rules or is not a good thing to do ??
Perfectly legit.
Give them your PayPal.
Remove the item as no longer for sale.
Nope you can literally just choose "no longer for sale" when you end the auction early.
It's perfectly fine as you can advertise things in other places than ebay