The main drawback is if something breaks from tenant use, no one will fess up to it.

Equity Multiple has some drawbacks as time frame is not factored in. 

What are the drawbacks and have you guys had issues arise after purchasing a property with unpermitted upgrades?

The drawbacks are that unless you upgrade your account, it does take several business days for the payment to actually clear in your account.

What are the major drawbacks?

The spread is roughly .75-1.00% difference in rate however doesnt go with out saying that FHA has some inherent draw backs too like its upfront financed 1.75% MIP and the slightly higher annual MI thats paid monthly .50-.85% per month.Given you're in the LBC the housing stock is a bit older there too so depending on which property you pick you might have more issues with FHA given older homes tend to have galvanized steel plumbing, clay drain lines, and a hodge podge or frankstein other plumbing types over the year when repairs were done by previous owners.

The drawback is its $150 bucks and I don't want to turn-off a potential buyer that is not "techie".I know its a minor detail, but what do you guys think - to Nest or not to Nest?

The main drawback of a 1031 exchange is the 45 day rule and having to identify the replacement properties, but if you are diligent and plan properly that is usually not too big of an impediment and can work depending on how motivated you are.

I have read a lot of posts regarding the benefits and drawbacks for HouseHacking and I have decided to take this as my first investment strategy.

Yes Red Bank is a great area to be but it does have it drawbacks.