Need your help now, about liquid inside cat
 

I really need your guys help now, few hours ago i go to upm vet to check my cat condition as it can't breath well. After xray the doctor said my cat is diaognise with wet fip (maybe) cause of the liquid inside its body. Because the doctor said they need to confirm with the liquid colour and blood for its disease. But it's costly (RM700-800) so i decide to bring my cat home. But now im worried about my cat because my cat not really show FIP symtomps as it already cannot breath well for 2 weeks plus its belly is not swollen and my cat still eats well. Can someone recommended me where cheapest place to bring my cat for the examination (100-200) is affordable