Assuming that you have a properly formed contract, the short answer is that they can refuse to perform, but there will be consequences.Those consequences normally play out in court, so it's not normally worth the cost to pursue it. 

It is normal to not have access to units until you are under contract with the seller and it is normal to include an inspection contingency in your offer.

There is normally a warranty in real estate contracts for specific items as well.The reality is: If you are buying your first property, what are the chances you identify something that the professionals cannot?

I’ve helped check on a property for clients before but that’s not a normal thing agents offer because that’s not their specialty.

They normally charge a customer the walk in price, and pocket the savings they get from their relationship w/ the supply store.I think we are the #1 customer at our markets Home Depot.   

If you google Rental Property Calculator that's what I normally use to get my numbers

That gazebo are normally for topical locations that do not receive such blasting heat like Arizona.

Also I have one guy whose alarm is apparently insanely loud and it wakes up others in his side of the building.

Think again.Sell a building at an outrageous price before the market normalizes, reinvest by buying up, buying more, buying a catamaran, or buying stock to preserve and build your wealth until the market normalizes, and then buy some more.My clients have been awestruck by the prices they've been able to sell buildings for in this market.

It is very normal for property taxes to increase when a complex is sold; especially one that has been owned by the same owners for 10+ years.