I only have two electric meters so there are technically no common areas. 

I've seen it happen a couple times.Most common materials for light renovation work are still the same here....paint, flooring, etc...

Its pretty common to pay the bank down 100% of proceeds so you end up with the last lots free and clear ..  

The most common way to buy an investment property with a low rate is to either get a conventional mortgage (fannie / freddie) or if you have equity in your home you can take out a heloc on your home and use that to pay for the investment property.

Very common.

Gasoline prices have not stopped rising in recent weeks in California due to the high demand, a common phenomenon at this time of year in the state (compounded by the urgency of nearly everybody to go somewhere, anywhere, now that the pandemic is unwinding).

If you are getting 15-20% IRR (which is fairly common) then you will be set up pretty well to keep growing your wealth 100% passively. 

In general what are common timelines for purchase to close?.

Is this common?

The standard brick side-by-side thats so common around here.