Public Liability Insurance for Hirers

I have a question about Public Liability insurance for regular hirers of rooms. We have a number of official clubs hiring rooms which is fine because they tend to have PL insurance under their wider club membership; WI, Girl Guiding etc. However we also have a few little clubs which are just groups of people who meet together and hire the rooms. One such hirer doesn’t have PL insurance on their home insurance, and has apparently been quoted £100+ for a PL policy. Does anyone have any advice they can shed on this? At present the hirer in question is considering ceasing her hire because of the cost. Thanks Sarah Read