@Shannon14 Hi Shannon. You will definitely need liability insurance from a company who specialize in short term rental insurance. As far as I am aware there is a company in the United States named CBIZ who do offer this sort of cover. There may well be others that I am not aware of. You must make sure that whatever cover you arrange sits well with your existing general house insurer as many are cancelling existing policies if they become aware that short term letting is occuring on their insured space!!
Another thing to keep in mind Shannon, insurers will only cover liability issues that arise on the insured property. If you allow guests the use of bicycles to get around your neighbourhood there will be no liability coverage beyond the perimeter of your property.
You appear to have done the right thing by getting your landlords pemission to host, now do the right thing by her and spand a good deal of effort in protecting both yourself and her......All the best.....cheers.....Rob