The cache container is a little tricky, but should be a quick find. could be a park and grab. It is not in or on the building, you have permission to park in the lot and search for the cache anytime. If there are cars in the lot, please be respectful, as there may be kids playing inside.
Walking trail across the street, be careful crossing the busy road if coming from the trail.
This one could be rough in the winter with a lot of snow cover, but that's your only obstacle. Enjoy!
The people who are often at this building know about the cache, so you don't have to consider them muggles, they participated in an introductory geocaching event, so they've already found it. Wheelchair accessible to get to the cache, will require a bit of a reach.