It starts by visiting the county MH dept, sometimes personal property, some times the auto title dept.In the end you want to "retire the MH title to real estate" so the land deed contains the MH as real property.

There could be other liens though, IRS, mechanic, etc, ask the sellers.Its too bad its already listed with a real estate agent as you can't cut them out of the deal.

PS: If anyone ever comes back on you for a mechanic's lien, you'll wish you had some paper documentation of having paid them.

What are the mechanics of that type of deal?

It's a rather obvious existing problem for which  the economics make no sense whatsoever.This is like asking your auto insurance company to insure your car with major damage after a big accident has already occured. . 

Level 3 -Reconstruction), 2) you are permitted (have or will get alteration permits,) 3) you are acting as the GC and have your trades (electric, mechanical, plumbing for the kitchen changes) identified.

Are they all on auto-pay?

And 36 Other Key Financial Measures 2nd Editionhttp://www.amazon.com/Every-Estate-Investor-Financ...Landlording on Auto-Pilot: A Simple, No-Brainer System for Higher Profits and Fewer Headaches Paperback – July 28, 2006http://www.amazon.com/Landlording-Auto-Pilot-No-Br...Stay away from Rich Dad hype books, but it's worth reading them to understand your competition's mentality. 

You only need this until the project is fully completed.If that contractor uses subs, then you need to get all lien waivers, this will eliminate the potential that the sub places a mechanics lien against your property because even though you paid the general, the general stiffed the sub and now you have to pay again.

If the bank will not require a haircut on their existing debt, I don't know the mechanics of the process all that well but it could ease the burden if the sale will allow the seller to pay off the loan in full.Regarding the potential basement units, I know that elevations vary in that neck of the woods.