Yes, the ol' gate keeper problem. That's why I never really liked commercial work. It sometimes takes awhile to get 'in' with the gate keepers. How about this... send them a HAPPY SPRING card and make it known it is from you and what company you are with. Do that by the end of the week. Then in a few weeks send an Easter card.
Then for the businesses right around you, buy 1/2 dozen glazed doughnuts and take them to the gate keeper. Just tell them who you are and who you are with. Don't try to sell them anything. Then send a Memorial Day card. Then a week after that send a letter (try to get the gate keepers name when you deliver the doughnuts) and tell them you will give them an extra x% off of any order if they order within the next 14 days. Say I can't do this for everyone but you seemed really nice and I'd like to work with your company. Ask them to email you to let you know if they are interested or not. Now what they will say is that they are only the secretary and they don't make the decisions. Now you have them.... ask what the person's name that you need to talk to and is there any way they could give you a good time to call that person. Now if you call the person and there is no answer on their end here is what you say.... Hi, this is Jenny.... DO NOT say who you are with... and I think you could help me with a problem I have. If you could give me a call back at 867-5309. Even if the gate keeper doesn't let you in or if the head person doesn't give you any business, keep sending a card every major holiday. And if you have the head person's name send the card to them now.
For businesses that aren't near you, you can't give them doughnuts but you can still send cards and then after a few cards maybe you can call... atleast you could get the gate keepers name when you call so you could address the card to her and make it feel personal. After 3-4 months I'd send a flyer with your specials. Make sure it's not crowded because they are only looking at it while on the way to the trash can.
But like I said... I never got in to commercial much because of the drawn out process. The only commercial work we did was from our residential clients.