Some boards exist solely to keep maintenance fees as low as possible, with virtually no attention paid to long-term maintenance and repair costs; then the owners sell out, leaving the new owners with hefty special assessments to replace roofs, siding, sidewalks, etc.

If that line is in the dirt anywhere, maybe it's leaking down vs. up, or leaking under a sidewalk or driveway.If the meter is spinning like crazy you should be able to hear the water running by putting your ear to the pipe and trying to follow it by sound.Other than that, I'm out of ideas on this.When you find it, let us know what was leaking.Good Luck! 

If it's a house in the city with no yard, maybe sweep or wash the stoop and sidewalk. 

Safety issues should always be addressed. ie, steps, railings, uneven sidewalks, etc.

I recently had a tenant trip on the sidewalk in front of the house and try to sue 4 months later.

(Text is written, but so is chalk on the side walk).

@Fernando Ramirez you need to ask the city what is required for all approvals and time frame, if you have to install curb, gutter, sidewalks, street signs, street lighting, any specific street design requirements, DOT requirements or permits, DWQ requirements or permits, permit fees, proffers, water/sewer tap fees and process, bonding requirements, inspections and CO process.

The township was pretty harsh regarding the certificate of occupancy, which really just meant repairs to the sidewalk and driveway / curb-- and in certain spots they wanted brand new slabs when patching would have been sufficient.

@Peter T.I implemented this and have 9 years without a call for change lightbulbs/clogged toilet/ smelly drain / broken window / shovel/salt sidewalks / bent curtain rods or bathroom towel holdersMove out inspections have no repair issues other than picture holes i walls.You may "think" it's ridiculous, but I'll compare my maintenance expenses with your properties any day.

The location could be a draw back like the hi-way next to it without side walk, unpaved road etc.