Hi, I have bikes at my host property.
Here's what I have discovered after 8 years.
It's a pain to service them and keep the tyres pumped. The liability of whether brakes work etc. If you are willing to do all that, then great!
If there is a bike dealer/rental location near by, maybe better to do a deal/promo with them?
Or, you carefully manage expectations that the bikes you provide at completely at the riders risk and you make no guarantee to roadworthiness/safety. But you need to tell them before they book otherwise if they arrive and there's a bike problem, they will be unhappy if they booked predicated on bike availability.
I'm lucky in that I have a big property and what I say now is, the bikes are not roadworthy but usable for the farm only. I leave out a pump to pump up tyres, and when I can be bothered, do it myself occasionally to see if there are any leaks and a tube needs changing (I've given up on doing it myself) and will take it to someone to do an overall service.
So for the 4 bikes i have, i only offer a few serviced so if they ask, I'll tell them which ones (maybe I should have a tag on them saying so actually).
More broadly I think its another option that's good but be careful in execution.
Btw I have been looking at a property to rent that has bikes to utilise myself, but I'm well aware if I get there and the bikes don't work, then I'm peeved.....
I think I would be happy to pay a little extra to be assured the bikes actually do work and are serviced to be honest.
Hope this helps
Regs
Mary