The other way is to close on the property yourself and resell to a buyer.

So 175K for purchase plus another 175K to build plus holding costs (12 months to be safe) and we can resell according to comps at 450K-500K, which will give us a profit of 100K-150K.

Meaning to commit to a DW like this you would need to be prepared to resell it where it is and not get a cash buyer or you would have to be prepared to get it to a piece of land like @Curt Smith and create a land/home deal out of it.

If your plan is to roll the capital gains over into a new investment property, you likely qualify to do a 1031 exchange (assuming you bought the property as an investment, not for resell).  

If the buyer is unable to buy after 4 years, buy back his "equity" if there is any for a discount or let him sell the house, then collect the profit or resell the condo on the same plan at the newly inflated price.I hope this helps!

With the current over-supply of property there may be some good opportunities to strike a good deal with a developer or re-seller.

I live in Indiana near the Indianapolis area and just doing some quick searches on MH's here, I have found some I can purchase and resell.

New laws have went into place earlier this year that limit and restrict seller financing when reselling to end-users living in the home.Since everyone's advice was great I am only going to add to what was already said.

Some come with 45-90 day deed restrictions about reselling the property.  

This is an area that is dominated by people who are really good at it so I usually leave it to them, there are wholesalers who specialize in reselling auction properties and they can be a good source.