Most of your deferred maintenance is going to come from road repairs and water/sewer systems. Get these looked at by professionals. Usually it isn’t difficult to find the right people in any area for any of these items.
For homes - Licensed contractors. Get them looked at by 2-3 contractors and get quotes from each one. Renovating a mobile home pretty much takes the lowest skill level in the contractor field. I renovated a few as a teenager and there is really nothing to it. FYI, I don’t think we ever came out of pocket more than $2,000 for materials on any one renovation I ever did. Adding in labor, $4,000 should cover a pretty extensive renovation on a mobile home.
For roads - Get them looked at by paving companies. Again, multiple quotes to get comfortable that you are getting the right price and getting told what the actual issues are.
Water/Sewer systems - If city, check the usage to see if there is a problem. If you don’t sense there are any problems based on usage, you’re probably ok to not even have it checked out. If you do sense leaks, have a plumber come out and identify them so that you can have them fixed on day one. Also, be sure you know what the lines are made of. If it’s a private system, then you will need to have them checked out by professionals who deal with those systems. You also want to get a history of the maintenance schedule the previous owner used. As an example, if a park has septic, we like to see that the owner had each tank pumped every 5 years or so. If its a well, we like to see that the owner complied with the law and had it tested regularly.
To cut your time down finding these professionals, find a few realtors in the area and get recommendations from them. Small time realtors are very generous with their time for some reason and they know the market better than anyone. They are a tremendous source of information about almost everything real estate related in your market.
When talking to contractors, you can usually get a long way with them if they think their getting the work. I usually tell them that we are under contract and want to get a handle on the issues. I also let them know that we want the issues fixed the day after closing. Knowing they might get some work out of this, they’ll sometimes come out to the property for free. Another thing that will save you money is not requiring them to write up some big, fancy report (Like an inspection on a SFH). Just have them tell you over the phone or in email what they see and what their price would be. Cutting down the amount of paperwork they have to do will save you money.