Not able to Record TDS when Applying credits to offset an Invoice

Not able to Record TDS when Applying credits to offset an Invoice

Hi,

I am a Landlord and I have rented out my building to a couple of Tenants.

The life cycle of a client would be as follows - 
1. They would give me 6 Months Rent as Security Deposit
2. I deposit the money into my account and create a Fixed Deposit.
3. I may supply some Materials / Services for helping him set up, which I would need to bill the Tenant for.
4. Issue Monthly Invoices + GST (18%)
5. They would Pay me Less TDS (10%, now 7.5%)
6. Once their term is over and they want to leave, I would break my FD and adjust any pending invoices, outstanding expenses, TDS and refund him the Balance Advance.

I am facing a couple of problems - (Please provide a Solution on how to account for this in Zoho, such that my desired results are achieved.)

1. When I accept the Security Deposit it keeps showing that it's a Credit available for adjustment of Invoices, but it is / should not be, since it's a Security Deposit. It should only be available when I deem it, once I get confirmation that the Tenant is about to leave. 

2. When I try to Adjust the Advance (Credit) towards Invoices, the Option to Record TDS is not available and I have tried so may work arounds, but I am not able to figure it out as that Option is not available anywhere. (In this case the Client did not pay the last 3 months Invoices, but did pay the TDS to the Govt.)

3. Every month, when I receive a payment less TDS against the Invoice that I raised and I have to record a payment, it highly annoying to adjust the payment after inputting the TDS.

Can you not have the Payments field auto calculate if I enter the TDS / Tax Withholding amount. Even if I am off by a fraction / Paisa it give me an error warning and there is a lot of back and forth, especially when you have many tenants and there is a difference between what is billed and what is paid.  

4. When I have to refund a Tenant's SD - I need to ensure that the following match to arrive at the final Refund Amount - 

1. Invoices & GST
2. Payments
3. TDS (Need a Way to Run a Report and be able to Save those Reports) 
4. Expenses / Bills

As of now this is it. Please provide me a solution for the above. 

Thanks,
Ram