When they arrive wear just a dressing gown when you answer the door, sit behind them while they're working on fitting the router.
As they start getting to work and are talking to you, reply casually as you remove the dressing gown (while sitting down) and loudly pour copious amounts of lube on to your semi erect cock. As they turn around to look at what made the noise you must slowly begin to masturbate while staring intently into their eyes and breathing heavily.
shud sort em out