If you inherited the property as a direct descendant (child, maybe grandchild) you should have reduced inheritance tax/higher threshold. I don’t think this applies to any other relationship (niece, nephew, cousin)
The property’s value is calculated at the date of death of owner so collect estate agent valuations, any offers to buy and comparable land registry information to support this.
Also collect any proof of payments for refurbishment before/after photos, but just hold these unless required as you want to keep the claim simple.
If you sell your current home you should be exempt. If ‘new’ home then becomes primary residence it will also be exempt after a period of time.
Sounds like a good plan, especially if you really like the inherited property and could live in it happily. It’s not often the tax system works for you. I’m sure you pay plenty of tax elsewhere.
Definitely talk to a solicitor. It’s not complicated so you don’t need get a fancy London firm.