This is very fun and rewarding! I can see how this can expand into more features like new items to buy, store expansion, specific customers/goals...etc. A lot of potential, I enjoyed it a lot :)
I agree with ironaxia that an arrow indicator could be helpful for at least tutorial purposes because I was also lost in getting in the computer room, I also had trouble finding the truck at first and missed like a couple of my orders. Otherwise everything else was great and well polished!