@Carrie Herring The mobile home is very old, so you'd be looking at the land. Before you make an offer, it's best to figure out your exit strategy.
I'm not sure if you're planning to buy and hold or fix and flip. If you're planning to buy and hold, then you'll have to check with the city and/or county to see what restrictions (if any) exist for that piece of land. You'll need the legal description and address for them to look it up.
Sometimes, if you plan to put a newer used mobile home on a piece of land or lot there may be restrictions (i.e. size, age, condition, etc) depending on the city and/or county. Your local zoning department will be able to tell you what you can and cannot do with that piece of land.
If you're planning to flip the land (with or without the mobile home), then you'll have to figure in the value of it and submit your offer accordingly to make sure there's room for you to make a profit.
Best of luck with the deal. Hope that helps!