Bed bugs are extremely difficult to get rid of, even when exterminators are called in, because they are resistant to so much now. It probably isn't an option for your client, but I'd tell her to find a new place to live and not to bring any old furniture to the new place. And thoroughly wash/hot(hot hot!!) dry any clothing/cloth items. With winter coming, leaving things to freeze for a couple weeks also kills the lil suckers.
Good thing for you though, they generally do not travel on your person (or pet, for that matter) and they really do tend to only come out at night. Leave any purses/bags in your car, or at least be sure not to set them on the floor (good advice for staying in hotels too - better yet, keep your bags in the tub). If you are worried about it, wear some PPE, maybe just the gown or such, if you are going to be sitting down. If it makes you feel any better, a good friend had a very nasty infestation that we didn't know about for some time; me and several other friends were at her house many times and never brought one back with us.
Other tips for your client until she gets some help in getting rid of the things:
- Freeze any books/paper items (heck, put the furniture outside and freeze that too for a while!)
- Double sided tape around the bed and around any areas your client thinks they might be hiding
- Place the feet of the head & foot boards/bed stand in small dishes of water so the buggers can't climb up (won't help if they are already in the bed, however...
- Grab a flashlight, wait for them to come out at night, and have a bug-smooshing party!
Hope you find some help for her!