But, we manage over 1,000 units, so we have all the features unlocked.  

I had a renter, hardship I didn't charge him deposit, but one months rent....day 2 he became enraged and moved out, broke the breakers, left everything unlocked, broke fixtures insideand demanded his rent back...and was very threatening...this guy thought since he paid no deposit he would get his rent back for not being there...some people do not think normally...be careful

I will just leave door unlocked that day and see what happens.

Cost of being lazy either expect your tools to go missing to take them with when you leave job site.The worker bees don't lock up well, window open, service doors, patio doors left unlocked and the more visible the project the more jerks it will attract. 

If you want to unlock some of the equity you drop in the house do Heloc on the new house.Or seat on the cash and wait until the buying market comes back around...

If you needed a locksmith to unlock your car on the weekend, he would probably take maybe 5 mins. to do that, once he arrived. 

I like landlordlocks as they give you a master so I only have to carry 1 key around to unlock every unit.

Yea HELOCs are a good way to unlock some equity and you can go above the normal 80% that way I believe.

As for the key situation: I leave my doors unlocked.

I have researched this and the worst I hear is that people forget to turn lights off and occasionally leave a door unlocked.