Frank always advocates that . People usually say 10 caps for parks but technically its (x% spread on top of your financing cost) . so in theory as caps rise, values drop and future purchase prices can decrease if rents and expenses are stagnant. There is a good chance that rents may rise (depending on market, cpi, economics, inflation etc) and the goal is try and find a park with operational efficiencies. So while there is a risk of value reduction, you are hopefully improving the properties value.
Ideally you want to buy at a high cap and sell at a low cap but timing is not an exact science so you want to control the things you can and recognize what variables are out of your reach. The big risk is when buying on skinny spreads with minimal value adds and locking into short term financing . I would be very cautious about this strategy if you feel that rates are to increase at some point in the near future. You may want to asses current debt and see if it is prudent to lock into desirable , low rate , longer term financing .