Your job, once you start real estate, is to replace your 9-5 job as soon as possible if that makes you happy.Money should not be an issue, if you know what you are doing. 

Maybe put some of that into a money market account or the stock market, so if an HVAC does go out in 2 months you can pull out $4-8k to replace it (depending on size, location, etc). 

On page 117 of Brandon Turner's "The Book on Rental Property Investing" he has a chart to calculate capex and I did my best to recreate this with more accurate prices (in the book he only budgets $5000 to replace a roof).

However, there's enough risk that many insurance providers are requiring replacement. 

We could have replaced it that day for $700.  

And then as part of the land business, I saw an opportunity to go into new construction in eastern tennessee area with the vision of building some to sell and building some to hold - to where I could replace all the equity I gave up when I sold about half of my rentals here in Illinois.So now I'm sitting on a hefty pile of cash.

If there are items you need to replace and they are less than $2,500, you can take advantage of the de minimis safe harbor election, which allows you to deduct those costs in the current year rather than capitalizing them.

They expect us to replace lightbulbs, won't change furnace filters and we also have lawn maintenance issues with them.

I have found another property of interest and I am considering selling the replacement property from this previous 1031 and using it to 1031 into this new property.

Yeah - if you think about it, the cost of replacement is the cost of replacement, regardless.