we are currently renting out 2 houses (the father-in-laws and ours) all moved in to this house and annexe.
As I did alot of business networking I knew a new agent who managed to let ours long term to a very nice couple who seem to be keeping the garden better than us for £35 pm (managed) and all works are to go through another gentleman I knew who can do alot himself but knows someone (via business network groups), who will do a good job and not rip us off if he can't.
The other house is in an area I don't know any businesses so through an agent again fully managed but costing over £100 pm, and using what seems to be the most expensive tradesmen.
Its all back to who you know not what you know and there is such a difference in agents and their charges, sometimes the smaller agents do a better job (they have to, to get established).
Good luck
K