i have a building could i rent it to a church
It is good that you asked because, no, we are not allowed to rent our property to a place of avoda zara. The reason is because we are forbidden to benefit an avoda zara. and by renting your property to the church you are providing the avoda zara with a place of worship.
H-shem should help you rent the building out to a better renter and for more money.
Avoda Zara 13a, Tur Y:D 143, Minchas Yitzchok 1-120.