If I won't to apply credit to tenants account what account should I use? For example I won't to give credit to a tenant for some repairs that he has paid and apply it towards his rental account...

Why not speak directly with the tenant and ask him how he'd like to have it credited?

I'm asking what acount to use as far as accounting is concerned, it is important for my records and managements reports after, cash flow, rent roll... I do not won't it to show up as income or as a payment in rent roll...