It would help to define what you mean by reasonably priced, and what level of amenities you desire, and how long you want to stay, as discount rates at commercial RV parks often start with the weekly rate.
Around where I live in western Louisiana most area roadside commercial RV parks have rates around $30 per night, $150 per week, and $375 per month, this is for what I would call 3 star RV parks, no real amenities other than maybe a laundry room, and a group pavilion, in overall fair to good cosmetic condition, etc. Add 15% or so to the above rates for parks with amenities like a swimming pool, monthly rates are typically not including electricity, though some in the area offer included electricity for under $450 per month.
This works out to be $12-$15 per day at the monthly rate, which is nearly impossible to beat on shorter term stays anywhere, in about 150 nights spent on my current RV since buying it in 2016, I can think of only 2 or 3 nights that I have paid under $15 per night for an overnight stop with electricity and water. This is not to say they are not out there, the neighboring parish (county), operates campground at 4 or 5 of their local parks, mostly river front or lake front locations, adjacent to boat ramps priced at $12 per night with a 14 day maximum stay.
2002 Safari Trek 2830 on P32 Chassis with 8.1L w/ 400 watts solar 420Ah LiFePo4
2017 Jeep Cherokee Overland & 2007 Toyota Yaris TOADs with Even Brake,
Demco Commander tow bar and Blue Ox / Roadmaster base plates