I probably would also paint the storage closet door red to match the front...or some other color beside white.

Wherever the main water line comes in if it's a closet or utility room I would do a main manifold right there. 

Be sure to check inside all cupboards and closets for items left behind.

I recently bought a property that within 3 months requires:A new roof: 16K-25K (not entirely a surprise I knew it's near the end of life span but didn't expect immediately leaks)Subterrainean termite termicide perimeter treatment: 1K (a surprise)Drywood termite tenting: 1.2K (not a surprise but didn't know the extent of damages)Power line weatherhead cracked: 1.3K (a big surprise)Interior doors and closet shelving from sub termite damages: $500 (a surprise)New water heater: $650 (not a surprise)So yes, you need cash reserves.

If the air handling unit is in a utility closet, just leave a few filters in there.  

Actually mine is in a crawl space and we have developed quite a relationship (she is a 1/3 horse Zoeller), but I do have a new back up ready to drop should she fail in my storage closet.

If you're trying to cut electric costs then why not go with a portable heat pump instead?

@Jon Huber I just want to get rid of it all without having to pay a junk hauler :)   I'd imagine it would be $700 or so to have a hauler go through every cabinet and all the closets and clear it out.

I'm not from your area so I may be wrong but let a trusted realtor, familiar with the area, give you the input on that decision.That being said, if you can steal a closet or some space from one, ideally on a wall that backs the plumbing-filled wall of your existing bathroom, to make a half bath either as a guest powder room or master 'ensuite', you're laughing.

If you need anymore info I got all the books and notes in my closet and don't mind sharing!