I have adopted piggies from the RSPCA Walsall as well; the first couple of home checks are always nerve-racking!
What the inspectors are looking out for is not a super duper place, just a normal home home and normal people. All they are making sure is that the cage/hutch is as requested (too many people have sadly been lying through their teeth to get hold of a specific animal), that the home is safe (in terms of boisterous dogs, cats and small children) and that the house is not the kind of place that you need to rescue them from again.
They like to meet the people in question to get a sense whether they will be responsible owners; if you have other pets, they like to see how you interact with them and whether they look and behave well kep (notwithstanding dogs often picking up on your nervousness!).
Just be normal yourself self as much as possible, and as long as your house is not a real tip, you will be absolutely fine! The recommendations on this forum comply with and often surpass RSPCA minimum recommendations, so refusals are extremely rare and most members pass their home check with flying colours.
Best of luck!
