last updated 30 Sept 2022

Gas Mileage (MPG) Miles per Gallon Gas mileage estimates vary all over the place the numbers above are the middle of the range.

These ranges may come from manufacturers people I've talked to typically get the low end of these ranges or lower.
The biggest factors that affect RV gas mileage are speed, weight, grade, wind, and ethanol.

Factors affecting gas mileage

How to Improve RV Gas Mileage [Fuel Economy Chart Included]
What is the Average Gas Mileage for a Class C RV?
Average RV Gas Mileage


Class B - Adventure Vans, Camper Van, Leisure Travel Vans,

The Mercedes-Benz Sprinter Van was the first popular vehicle of this type.
Now Ford, Dodge Ram, and Nissan have similar vehicles.

There are many companies customizing these vehicles and you can order your own configuration.

The basic shell costs as little as $30,000, but you can spend another $40,000 or more for Off Grid Adventure features bringing it to $70,000.
The tricked-out vans they had at the Tahoe show started around $110,000.
For a premium camper van with four-wheel drive you can expect to pay anywhere between $160,000 to $200,000.
The four-wheel drive The Winnebago Revel starts at a whopping $174,000.

What Is The Average Cost Of A Camper Van? (New, Used and DIY Builds) | TrailAndSummit.com


Some Specs:
Measure Mercedes
Sprinter
Ford
Transit
Ram
ProMaster
Nissan NV
Length (in.): 233 - 290" 236-264 213-251
Width (in): 69 69 73 80
Wheelbase (in.)1: 144 - 170" 130-148 136-159 146
Interior
height
68-79 72-82 76
Cargo Space (cu ft) 319 - 522 404-487 420-463
Drive 2WD & 4WD AWD & RWD 2WD
GAS MPG 19-24 14-18 13 11-15
1. Some will have a shorter wheelbase and more overhang in the rear for a smaller turning radius.

The average traditional RV usually gets a paltry 7-11mpg. So any of these cargo vans saves between $10-15,000 for every 100,000 miles driven.

Batteries:
Most have an array of lithium batteries; eiter 12, 24 or 48 volt. The trend is toward 48 V>
You need to calculate what appliances you have and total usage. A combination of batteries totaling 300-500 Ah (Amp Hour) are normal.
This could keep you off the grid for 2 days. This is if you don't use your air-conditioner if you have one.
Absorbed glass-mat (AGM) batteries are replacing Lead Acid batteries for cars, but both Lead Acid and AGM batteries can only be discharged to 50% so you need twice as much capacity as with lithium.

You can get a second alternator run from you engine, solar panels or a generator to charge the batteries.
What about electric vehicle (EV) charging stations? There are EV Charger Power Converters, but they may not be legal.

. Calculating battery size | SrinterVanUSA.com
What size and type of batteries for you camper van build | ALpinVan

Toilets:
Cassette toilets are popular instead of built in holding tanks. They hold about 4 1/2 gallons.
They can be dumped in RV dump station or public toilets. In the wilderness follow the procedures you would when camping. You can use chemicals to avoid the smell if you using it for #2,

Cassette Toilet Review - What Is it? How Do You ... - YouTube

Links:
10 Comparisons between the Sprinter, Transit, ProMaster & Nissan Vans | Via Verde Vans

Mercedes SPRINTER VS. Ford TRANSIT VS. Dodge Ram PROMASTER - WHICH ONE IS THE BETTER ADVENTURE VAN? | FVC Flatline Van Co.

The Sprinter Camper Van, a Review of Class B Mercedes-Benz Sprinter RVs | Adventure.com

Adventure Van Expo Series shows


Links:
How Much Does It Really Cost to Own an RV?
Average RV Cost — and What Else to Know About Buying and Owning an RV