Will, Probate and Confusion

[Sammy986]

My father recently died as a widower and the property was his in full.
I as his son have lived with him in the property for 48 years. I have one sister who moved out decades ago, whom my father disowned.
I have found his will and states that I am the sole benefiiciary, although in his last days he did mention that he changed the will giving her a couple of percent, hes mind was muddled at the time, so am not sure.
The value of the property is around £430,000 with very little else in terms of cash, cars or investments. (Basically nothing else)
I'm extremely low on cash so how can I start the probate procedure in the most cost effective way?
Is there any issue if she gets the probate going before me with her few percent?
Also is it true that the threshold for IHT is £500,000 if children are the beneficiaries?

[Sammy986]

Also how do you find the solicitors whom my father made the will with if I dont know who they were?

[Sammy986]

If its just 1 property, 2 bank accounts with nothing in and zero other valuable assets, can the probate be done by myself?

[atticus]

The will might offer clues to the solicitors. Who are the witnesses?

[Sammy986]

The will might offer clues to the solicitors. Who are the witnesses?

Nothing on the will in terms of solicitors name or addresses, just a phone number on the envelope which isnt regognised. The witnesses are my next door neighbors of 25 years.

[atticus]

No letters or invoices amongst your father's papers?

You can write to all the local firms.

[dslippy]

Speak to your neighbours