I am not sure I would ever call a mobile home an investment. Mobile homes depreciate over the years, and unlike some cars, they never become classics and reverse the trend. That having been said, there are some advantages to owning a mobile home.
They tend to be cheaper than houses for similar floor space. A mobile home can often be purchased on a lower down payment both because of the lower price, and the fact that they have dealers selling them that are aggressive in negotiating easier terms with banks and finance companies.
By purchasing a mobile home, you get the feel of home ownership. If you can pay it off quickly enough and keep it in top repair, you should build a little equity. By living in a mobile home for less than 5 years, you may actually recover most of your money because inflation will let you sell the home at close to what you paid for it. New mobile homes will cost considerably more than you paid. If your home is in like new condition, buyers will be willing to go for the used home to save money, sales taxes, and personal property taxes.
By keeping your mobile home, you eventually pay it off. If you have set up the loan correctly, a mobile home should pay off in 15 years or less compared to 20 to 30 years for a house. With the addition of decks, add on rooms, and/or a shingled roof, mobile homes can be configured to look and feel like a traditional house.
If you have a little spare cash, you can actually relocate the home if you really like it and get an opportunity to purchase a lot or acreage. Many people choose to live in a mobile home on their own property while the build a house nearby. They then sell the mobile home to someone who relocates it.
Double wide and modular homes can be moved onto a basement. With upgrades to cabinets, insulation, floors, and wall coverings, they can serve as a house for decades. With a mobile or modular home, you know exactly what you will have when you buy it. They are a quick way to get personal living space with much more freedom than an apartment. If you have pets or children, this can be a big plus.
You may still have to pay a lot rental in addition to the payment on the mobile home. In exchange for the lot rental, things like trash pick up, sewer, and water are often included in the price. In some parks, it also includes yard service.