Was the Manufactured home new when you bought it, if not, FHA becomes complicated since the home would not be original to your location. You say you owe $148K, what do you owe that on, the land? You may have to go Conventional with 20% down. Remember the 3 C's of Lending, Collateral (the property has to qualify), Credit (your payment history), and Capacity, your income and ability to re-pay the loan. Give us an update when you can.
To answer your question, this would definitely be a refinance since you already own the home....and there's really no difference comparing a refi to a purchase loan..
Best of luck,
Alpine Mortgage Planning
Have a great day.