Help save my cat Eeyore

My cat , Eeyore, is in the ER with a very severe urinery tract infection, which came on very quickly. He has to have many tests done, such as blood work, kidney  and bladder testing. I really really hate doing this to be honest but this is costing me almost 2 mortgage payments and as many of you know, I live alone without a roommate and this emergency was very unexpected as my cat is usually very healthy. Help is much appreciated.