Yes mate. Makes motivation go through the roof, also you would need to add an extra third to your workload which motivates for the canvassing side of things. Those who say headache are the guys who couldnt organise it properly, theres nothing like pulling upto a row of jobs and just sitting back now and then while your lad just bashes it out. You will be able to get an extra £100-150 done a day if both working throughout too. Can only think of positives for your business with getting an extra pair of hands as long as you can afford to take someone on.