Our inspection uncovered that the smoke detectors were battery powered.

doors - if outside doors=350 a door or inside doors=125 (or the cheapie 35) per door no labor.washer/dryer - just the electric cables 20 each no laborkitchen outlets - just GFI is 20 each. no laborpaint/knobs - 1.50 each knob. no laborfaucet - decent one 80-150. no laborplastic lining - no ideadetectors - either batteries or new detector at 10 to 49 eachgarage door - 1 hour labor cost for Atlantaoutside cleaning - 300 to 500 for cleaning.Do not misunderstand me, you can get the job done by yourself cheaper, but hiring two guys and the cost of materials is surprise.

And batteries, last for 1 year, 5 years?...

Junk yards typically have battery acid leaks, motor oil leaks, gasoline spills and other items relating to electronics.

LIFE-CHANGING ACTIONS here.STEP 1-20.You need to get you personal home rent-ready... not overboard updating, just rentable... clean and painted etc.Fix any leak faucets, loose doorknobs etc NOW, so that when your PERFECT tenant moves in, they won't be calling you to fix those.Put in new 5 Year Lithium Battery (write the date installed ON THE OUTER SHELL) of SMOKE DETECTORS (draw faint red stripes across the front outer shell of smoke detectors-- red means fire or smoke-- when the smoke clears (if the house didn't burn down) it's ok to reset the smoke detector and finish cooking dinner.ON CO DETECTORS (draw faint gray stripes across the front outer shell of a CO--teach your tenant the gray stripes mean DEATH-- if that alarm EVER starts beeping, they are to immediately raise windows , open doors and call you---even if its 2am--- A REPAIR MUST BE MADE or people can DIE-- little children and elderly go first

That bad stuff happened just 2 days away from scheduled surgery to fix that module in my head that failed.Luckily I was married and owe her a bunch.  

See if that property management company is keeping up to date on the latest laws (for instance, look to see if a newer lease still requires the tenant to replace batteries in smoke detectors -- it's now the California Landlord's responsibility).  

They beep when the battery is about to die or when kitchen fumes are abundant.

I have found that the cheap, battery powered fake cameras with the flashing red lights are a great deterrent.

(Not "manufactured" homes.)Modular homes are built on foundations, with various "modules" brought in on trucks, and generally look like ranch style homes.