Conventional lenders don't finance manufactured homes.
Also, conventional lenders don't go below about $50,000.
There are a few specialized lenders who'll lend on manufactured homes, especially if it's a newer one. But, as noted, the interest rates will be higher. If the home is in a park, as the park management for recommendations on lenders. They'll know.
Ask the seller if he/she is willing to owner-finance.
Alternatively, there is private money out there, but that's expensive too. Probably in the range of 12%-14% per annum.
Hope that helps.