I was doing some research a while ago about stuff to put on the (cement) floor of the attic of my parents house. To my surprise I found that covering the floor with proper wood-imitation laminate from the local DIY store (or IKEA) was cheaper than painting it with a paint designed for cement/concrete. Faster too.
What I mean is, be creative. It might be cheaper for instance to pick up a batch of 30x30 cm street tiles, paint them white using anything you've got available (a cheap bucket of latex will probably do just fine) and lay them in the grass spelling out the name. Just as visible from the air and much easier to maintain.