A toyhauler seems like a good solution but the ramps are often too steep and have a high lip where they meet the ground. Class As work the best. Both Winnebago -
http://winnebagoind.com/products/specialty-vehicles/2016/ability-equipped/overviewand Newmar make accessible motorhomes -
http://www.newmarcorp.com/motor-coaches/gas/canyon-star/wheelchair-accessible/ Used accessible RVs are also available -
http://www.disableddealer.com/item_search.asp?category=1020http://www.handicappedtravelclub.com/htc-classifieds/browse-categories/51/rvs-travel-trailers/ Your friend may be interested in this facebook group-
https://www.facebook.com/groups/rvingwithdisabilities/ I use a wheelchair and post information about accessibility on my blog. Please give the link (in my signature below)to your friend.