We replace the whole device every ten years.

I know this because I have installed these systems myself and also talked  with 2 engineers about it.  

We currently have a home warranty (through Old Republic) in place that would cover the cost of replacing or repairing the water heater should it break.

I used to live across from an engineer that thought all agents were "blood sucking vampires".

But the county replaced all the windows as well!

We are replacing older top loading Speed Queen washers with front loading ones and always trusted the reliability, dependability and quality of Speed Queen but they must have changed something in circuitry boards. 

It turned out the furnace was shot and a large cast iron waste pipe was rusted out and needed to be replaced.

First, you originally are buying the property with cash, so the purpose of refinancing is to get your cash back to use again.Second, this is nothing like replacing a credit card payment with another credit card payment.  

I don't ever plan to make this a full-time gig as my career as an engineer is fun and rewarding, but I like the idea of owning multiple properties and the financial flexibility that comes along with that.My wife and I purchased a new construction home in 2009 and took advantage of the $8k homebuyer credit.  6 years later we are selling our home at roughly a $15k loss, which is certainly unpleasant.  

I have a full business insurance policy for both contents (cost to replace) and complete liability plus another for workman's comp for freelancers I may hire on a one days basis.