What tax is due re property in trust - 9 years after probate

[Roses10]

Probate granted 2008. As per the will, one property to be held in trust for four trustees (deceased's cousin and her 3 grown children). Deceased's husband resided in property and the will stated he is to remain as such until his death. He had to go into a residential home due to dementia 18 months later. All parties of the aformentioned trust agreed that the deceased's cousin (a trustee) would reside in the property, rent free, until any change in circumstances. The 'tenants' have used their own money to improve and maintain the property to a high standard. The deceased's husband had his own private funds to pay the private residential home so his costs were taken care of, although the will did make provision for any rental proceeds to assist in his care?!?
Each trustee aswell as one other beneficiary received £50k in cash inheritance at the time of probate.
Advice at that time of probate was that no inheritance tax would be due (property value at the time of probate was £190,000)
The deceased's husband has recently passed so the trustees want to transfer the deeds in to their names, but are confused as to what tax may be due?
Should inheritance tax have been paid?
Could there be income tax due based on lost income from the property not being rented out?
Is it now due because the property deeds are changing and the death of the deceased husband has triggered it?
It's 10 years since probate next year, how much would the 10 year anniversary tax be?
Current property value £290,000. does the property value increase since probate change things?
If no-one has funds to pay HMRC if tax is due, can they force the sale of the property? Would there be a time restriction on this?
HMRC website sooooo confusing because this situation has so many factors

[AGoodman]

1. No 10 year anniversary tax on the trust as it is an Immediate Post Death Interest and therefore not relevant property.
2. There are no deemed income provisions.
3. It may be necessary to submit an inheritance tax return but it seems very unlikely that any tax would be payable - you have not mentioned the full value of either estate including the property - but the total aggregate nil rate band for the two estates would be £650k. There is also the possibility of 2 x RNRB of £100k each (£200k) if the children are also the children of the husband and they receive the property outright on his death.