Best time to Value your intended residence?

[sober]

A couple of years ago I bought a small run-down flat above a shop together as one freehold, (funded from savings and family etc), with the intention of living in the flat after renovating it, and using the shop as my office for my small company on nominal rent.

I took me longer than I had expected due to shortage of money. When it was done up 2 years later I had to just rent it out from last May. Mortgare adviser told me I need at least six month record of rental income before I will be eligible to take out a loan on it.

Can some one please advise what value I should realistically expect to raise funds up to for all interest to be an allowable expense. Would it be the purchase price only, or price + costs, or valuation from the time I actally rented the flat out.

thank you for any help

[newton1]

If you intended to rent the small office from the start,
I don't think you can raise any more than what you paid for it - to deduct interest.
Is there a way you can prove your intention?
Can you separate the loan on the flat from the rest of the loan?

My accountant didn' allow me a penny more than the original mortgage on my ex house years ago.

I wish taxes were more scientific, I would know more about it !