Even in a lower priced investment property, like a small SFR, what does the investor without a contingency fund do when say the ac or a furnace need replacement?  

Let's use an example of replacing a leaking kitchen faucet (assuming it can't be repaired):You can easily find out how much the materials are by going to the Home Depot website and picking one out.For labor we Googled, "How long does it take to replace a kitchen faucet" and this is the answer we got:AI Overview: Replacing a kitchen faucet can take 30 minutes to several hours, depending on the faucet's complexity and whether you're doing it yourself.

So I would caution everyone to make sure the replacement cost for your improvements will realistically cover your actual replacement cost in the event of a total loss.

In my round-up note as we moved out, I mentioned that the ice maker in the fridge hadn't worked in many years and the model was known for issues so we just never replaced it. (8 year old fridge.) 

The current one lasted 8 years and needs to be replaced (as per what our property manager is saying)I heard front loaders could leak, so I typically only do top loaders for rentals.

Now do not get me wrong, tech has its place in real estate, but it’s not a replacement for expertise.

If you're insuring a home to replacement cost, insurance companies don't care about appraisals or what the home is worth.  

There is no requirement for @John Gillick to replace debt with new debt. 

In a 1031 exchange, the replacement property must exceed the total sales price of the property sold ($700K in your example), not just your equity portion.

doesn't make sense to treat the house then throw all the stuff away, and replacing the carpet and repainting the entire house2.