My LTR income has provided the cashflow to quit my job as an electrical engineer.  

Additionally, you'll be making a lot of decisions on the plans today that will drastically affect the cost of your build later, so get a GC lined up now that you can run questions past like gas in the building or all electric, if it's a duplex how do I get away with no house meter for the electric so I only have two meters and not a house meter you have to pay for, etc.

I do not have a sheet but I typically budget $150 for lawn, $150 for pool if applicable, $100 for cable, $100 for water, $300 a month for electric (depending on property size and your local utility costs), $50 for pest control, and another $200 per month in misc. 

EDIT: take a look at the SAILFLO 2000 GPH 12v Electric Bilge Pump. 

Hey @Devin Bost, I would highly recommend a few things to help with this. 1) Have systems and processes lined out for any emergency you can think of.2) A spreadsheet of subcontractors/ vendors that could handle the situation that arises (plumbing leak, electric out somewhere, etc.)3) Your cleaning team and handy person should be utilized for some things.4) Something like Breezeway can give you 24/7 support around your property with a dedicated phone number line.

"Dusk-to-Dawn" electric eyes and timers can be helpful, but don't replace personal surveillance. 

One great example is framing crew comes in....frames up the house, plumbing and electrical crew comes in and does their thing....leaves all their 1/2 finished cokes, Gatorade and beer cans and 1/2 eaten lunches sitting on the framing.   

I find myself constantly learning and reading about real estate investing, the bug has definitely gotten me!

When it comes to foundations(or anything structural for that matter), plumbing and electrical, it's better to bite the bullet and do it right the first time.

My townhouse is all-electric with no garage, no fireplace, and no bbq grill, so no source of carbon monoxide.