I was a trustee, there were three, one being the Bank of hell The Bank did all the practical legal adminstration and bossed us about advised us re investments etc. The Bank was paid (an extortionate amount) from the Trust's funds, the trustees were not paid other than expenses.
As a trustee (l think with property there has to be at least two trustees) you can appoint a professional company to deal with the rentals/tax returns etc if you don't want to do it yourself, obviously they will be paid from the trust (possibly out of the rental income if that's the only funds). You can do it all yourself, if you have the time and inclination (if you are renting out property you will in effect be the landlord, it's time consuming and thankless, though you could possibly pay yourself out of any funds).
I wasn't asked in advance and had no knowledge of the trust until the death of the person who set it up. I could have refused but was presented with a fait accompli. It was a huge amount of money and the responsibility and hassle were a burden. Once you have accepted the role there is no escape. That's my experience in a nutshell, never again, it was the last thing l needed to have to do whilst coping with bereavement. I would think very carefully about it.
This link explains the role well.
What is a Trustee in a Will? | Kings Court Trust share.google/2GK3VEzD39dqLBKbZ