Any local agent(s) can help and he/she will need to see the property first before establishing a price--you also need to be aware of comps-- recently sold similar properties in the immediate area--after reviewing the data a determination as to a fair listing price can be made.
It's nice that you are in a family park. It opens you up to more buyers. I currently have a sale pending on my listing in Napa Valley Moble Home Park on Pattie Way. I have sold several units in both Newell and Salvador parks. I cannot tell you what the value is without more information but would be happy to meet with you and do a market analysis on the property. How soon do you want to sell and/or put it on the market? It sounds like you are in a great location within the park.
I live in Napa and am very familiar ( live close by ) with Newell Park and your home should sell for approx $60,000 to $75,000 depending on condition. I could look at it and give you a better idea , but that will be very close based on your iformation. Glad to assist . Regards Al Sovey 337-0896