You need to discuss this with your mortgage lender ASAP. These types of loans are not easy to get. You will probably need to go FHA, as long as the foundation is permanent and meets FHA guidelines. If it doesn't, the seller will need to retrofit it. Also, that mobile home needs to have been moved only once, onto that site. If it has been moved more than once, you will have great difficulty finding any financing. There just aren't that many lenders who want to offer MH loans anymore. So before anybody gives you estimates, they will need to know about the foundation.
Good luck! Barbara Coker, NMLS Licensed loan officer #228545