check out www.gumtree.co.uk they have lots of furniture and freebies too!
Get her involved in the decision. Tell her you need more room and ask her to help you find ways to make more room. She will most likely see that the big furniture are problem and volunteer to move them. If not while you guys are looking over your roo...
There are several tour operators in Lancaster. I'm not sure which one you are going on. The tour operators are not amish, but have made a "deal" with some Amish folks. You may be lucky to be going on one of these, in which you will visit a real amish...