A few things.
First:Getting the website IP costs money, there is no way around that.
Second:You really need to change it away from 'hiring' to 'looking' for, because 'hiring' means they will be paid.
Third:If they are admins, they don't need diamond blocks or ingame things, as admins can spawn things. If you do not give them the power to spawn things, then that's not admin, that's moderator.
Fourth:If your server is less than 5-10 people, you don't need a moderator, and if it is more than 5-10 people, you cannot run it off of a home computer, which means spending money.