Not sure on the apartment question, but in terms of dog friendly neighborhoods, there are several dog parks spaced throughout Longmont. Here is a link to their locations and rules: http://www.ci.longmont.co.us/parks/park_list/dog.htm . The 2 I've seen are the ones at 21st and Frances, which is just a couple of blocks from the large Garden Acres Park and the one at St. Vrain Rd. and Airport, this is a few blocks West of Airport Rd.. So if you are in an apartment that allows dogs and it is near one of the dog parks, that would make it more convenient. Plus with 3 additional dog parks dispersed around town, you can easily access one from almost anywhere in Longmont.