If there isn't a "good" place to put a hardwired SP, I would go with the external or portable type.
Right you are Evereddie, open neutrals, reversals, not to mention low and high voltage are probably the most common killers.
These good surge protectors, do much more than send a sudden surge of voltage to ground. They even let you see Voltage, Frequency, Amps and Error Codes.
I saw the aftermath of a burned down MH, after the park maintenance crew reversed hot and common into a row of pedestals that the unit was running on. If the people had one of these, it would have shutdown the power to the unit very, very quickly.
The link is to PI 30 amp portable. Don't be tempted to get the cheaper units. I personally like dealing with TechnoRV. I have bought several items through them and the personal attention is second to none. They are RVers and only endorse a product that they have experienced and know what they are talking about (and selling). It has recently changed hands, but same type of good people.
Portable 30A Surge Protector & Voltage Protection