The basement also has its own walkout entrance on a concrete patio at the back of the house underneath the deck.

You typically want to make sure the land is suitable to support the type and size of structure proposed, so you want to get some soil test borings performed by a local geotechical engineer. 

The environment we grew up in is the soil. 

Harder work if you're not removing joists, from an access perspective.I also was not formally trained as a structural engineer, so my terminology may not 100% be 'on point' but if you can imagine a new 'ledger board' system that is supported by these 4 footers, and then using joist hangers to support the new joists, that hopefully gives you the visual.I personally would not mess with supporting something running laterally underneath existing joists, given that you are replacing some joists.  

Check with your agent.Mobility: To be mobile the mobile home should still have the tongue either attached or stored underneath and have the road wheels and axles underneath as well.

The actual siding is fine, but underneath the wood is rotting due to age

VRBO has the nightly rates for individual condos on their calendars - scroll down to it, and you'll see the rates in little type underneath each calendar date.  

If there is at least 2-3 ft of soil below the current slab and the foundation, we would only need to excavate, place new insulation and gravel then a new slab.

The sewer line had a 30 foot span that was not supported underneath and the line looked like a banana!

My socks felt soiled when I left, from walking the house.