There are many answers to this question, and the only real answer is what it costs YOU to live a nomadic life.
The general pattern is you can do things a cheap way, an average way, or an expensive way depending on your lifestyle.
|vehicle||what you own||what you buy||what you finance|
|build||minimal build||DIY build||factory build|
|food||scratch cooking||cooking with some eating out||eating out|
|campsites||boondocking||public campgrounds||private campgrounds|
|fuel||staying put||moving occasionally||always on the go|
In this category you can find members of the Cheap RV Living forum, Social Security beneficiaries, disabled veterans, private pensioners, and minimalists. Boondocking or stealth camping is the norm. A campground with hookups is a rare indulgence. Often found in the company of a dog, sometimes found in loose groups of fellow boondockers.
Modern working-age nomads usually get by in this range. They will sometimes boondock, sometimes park in Walmart lots, and sometimes stay in reasonable parks with hookups.
It is possible to spend way more than $1500/month but in general this category is inhabited by the comfortably retired. They can afford to drive luxurious RVs and put down anchor in nice campgrounds (or even resorts!) with full hookups.