I'm sure it would be hard for you to say NO as some posters said you should. Or that *doesn't work for me*. That sounds snooty. No need to say it.
Or even offering a list of hotels for them.
It may even be hard to say you need the added income that you'll be turning down during their stay.
I know your friend is coming this week, so the 4 days you gave up is just unfortunate.
From this point on, just say in a spur of moment conversation when someone calls that your district is experiencing a lot of absenses and you're really needed.
Make up an excuse that you've committed for someone on maternity leave. That will give you more time to free up till the school year is over.
I wouldn't feel comfortable with guests at my home if I was at work all day--I know that wouldn't bother many, but I'm just that way.
If they do come during the school breaks/summer months and want to do *excursions*, choose whether you want to go or not. They shouldn't be insulted by that.
You probably started right out the gate offering to pay to go to places as they were your guests at your new home. But they should've reciprocated in some way. Don't back down if they do offer. Let them know how much that would mean to you if they did. They'll *get it*.