It just never occurred to me that she would want to take a house prior to seeing it., or that that was an option.

Something else that hasn't occurred to me?)

Since you did not have an early termination clause/ liquidated damages in your lease you can charge the tenant rent that is owed at time they vacate and rent as it becomes due until the unit  is re-rented or the end of their lease, whichever occurs first.

However, sometimes circumstances occur where they will be late.

My fear is that I buy this and later on something like that occurs.

We want to legally ensure that we are protected if in fact the tenant does use the garage as a bedroom, and if something were to occur (i.e. fire, carbon monoxide issue, etc).What would be the best way to inform the tenant that the garage is not to be used as a bedroom due to improper egress and fire risks, while maintaining protection if they do continue to keep as a bedroom behind our backs (i.e. if they state it is simply the storage of a bed and not being used as sleeping quarters... as there is really no way that we can prove otherwise as we are not there at night obviously).Thanks in advance!

I think that is where some confusion/bad reviews can occur.  

There is no law in Texas requiring you use any of the above to buy or sell real property...it's up the consumer and how confident they are they can weather a huge financial mistake should one occur. 

Not enough cash flow and unexpected problems do occur, i.e. broken pipe, plumbing concerns, etc. 

My wife and I went out estate sale shopping (for houses) and missed the one occurring at this address because of all the other ones we had been to that day.