Spray is not very stress free
Frontline spot on's are good - they work well and are now competively priced as they can be bought online.
If you want to buy prescription treatments you have a big choice, some treat round worms and ear mites as well as fleas.
A well priced combination is drontal for worms and frontline for fleas.
Avoid any supermarket/PAH products eg. bob martin, sherleys, johnsons