I'm a bit low on money at the moment and can't really afford to send out anymore books for a while. But I have 7 books sent out and will have creidts for a while. If I put my account on vacation hold, will I still be able to get wishlisted books that are posted and such?

If you put your wishlist books on AutoRequest, they will be requested for you while you are on vacation hold assuming you have the credits for them. 

You can receive your WishListed books while on Vacation Hold if you put them on Autorequest-Yes, and have enough credits to cover any that come up.  (You won't receive any offers for your WishListed books that are on Autorequest-No, however, while on Vacation Hold.)  If an Autorequest-Yes book comes available, and you do not have the credits in your account to cover it, you will have 48 hours to obtain the credits and then accept the request...

You can also just go into your bookshelf and put all the books on hold. All you have to do is go to the upper right corner of your bookshelf, click "select all" then click "hold". If you have more than one page of books, you will have to do this for each page. I did this after sending out 24 books in less than a week, but I don't want to put my WL on auto-request.

You can also just go into your bookshelf and put all the books on hold. All you have to do is go to the upper right corner of your bookshelf, click "select all" then click "hold". If you have more than one page of books, you will have to do this for each page. I did this after sending out 24 books in less than a week, but I don't want to put my WL on auto-request.

This is not recommended unless you have books that are pretty rare in the system. When you use the individual Hold on your bookshelf, all of your books are removed from the FIFO lines and are essentially reposted when you take them off of hold. If you have books that are pretty heavily posted in the system, you will keep putting yourself back to the end of long lines.