For the common wall, I think you best bet is using a de-coupling adhesive like Green Glue Noiseproofing Compound.  

Originally posted by @Joe Villeneuve:You could retire in 3 years on 150-200k per year...if you understand:1 - Thoroughly what Einstein called the "greatest invention on the 20th century", and how it pertains to REI2 - How to use "Non-lienable debt"3 - How to design a plan based on your financial goals (needs)4 - How to incorporate "duplication on steroids" into your plan5 - How to stick with that plan.6 - How money works Reader's Digest explanation:1 - Compound Interest2 - This is a much longer explanation.  

That doesn't mean it is a good strategy.Why at the point where you have the least experience and are most likely to make mistakes would you compound that with high amounts of risk?

BUT where the magic happens is in COMPOUNDING on the inflation side. 

I have had maybe two outfits that are considered "nice", and they both got ruined from joint compound, paint, and caulk. 

Could get both, maybe convert to AirBnB compound if you file for a variance with the city? 

I can't remember if we used drywall compound or wall texture but they both can be washed off with a drywall sponge if you hate it (but just practice on a garage wall until you get it down..tor a sheet of drywall..the materials are cheap).  

The texture is just joint compound that can be bought in a box and mixed with water in a 5 gallon bucket.9.

Can this hole could be fixed with just the joint compound/mesh method, instead of the more involved method where you cut out a square of drywall around the hole?

You can have one property paid for free and clear, which is clearly a strategy some people use with great success, or you can buy 10 or 15 mortgaged rentals with good cash flow and take advantage of compounding.