I learnt the lesson the hard way.

And like you I have learned my lessons by stepping in pitfalls and land-mines over the years and have made conscious effort to not repeat my mistakes and take my licks..

I have recently learned the above lessons and acting out my action plan and would be happy to brainstorm with you.Cheers!

Probably less on Amazon.I bought my low flow shower head from the city of Houston for $5.

Some lessons, even the failures can only truly be learned through experience. 

Lesson learned here, adapt to each property!  

I've already learned that lesson the hard way both through just the renovation of our own home (overpaying and underestimating costs!) 

I think a valuable lesson here is to do due diligence on all parties and have advisors from outside the transaction. 

Are there lessons you have learned but the Bank needs more proof?

I feel that the most important overall lessons they taught me were to:1) Live a frugal life, because it doesn't matter what your income is, if you can't save anything, you won't be able to invest anything.