What to look for

Size

Motor caravans are sized according to their number of sleeping berths - usually the higher the number of berths, the bigger the van. But most new models are built for two people, no matter how many "berths" they have.

Neil Whithear, owner of Christchurch dealership Barron's South Island, says: "A motor caravan may have the facility to accommodate extra people, but most manufacturers only build retail vehicles designed for two people to comfortably live in."

When it comes to deciding what size van you need, a spokesperson for Maui Direct (which sells ex-rental motor caravans) says it's crucial to think about who'll be using the van - and how it'll be used.

"It's really easy to get 'scope-creep' ... where you want a van for weekend getaways but end up with one large enough for your whole extended family because it's just conceivable that you might take the whole family away one day. Be really clear about understanding your principal use and stick to it."

Diana lives and travels in her motor caravan full time; she got a van large enough to accommodate four people because she spends a lot of time in it. Resale value was also a consideration, as larger vans may be easier to sell and attract a higher resale value. Ross has a three-berth van, which he chose because it's large enough to have a permanent double bed (so he doesn't have to fold it out and make it every night) yet small enough to comfortably park at the supermarket.

A larger motor caravan can be several tonnes gross weight, so you need to be comfortable behind the wheel of such a big rig. You also need to think about storing or parking when it's not in use.

Features

Motor caravans can have better features than a house - double glazing, gas central-heating, and a satellite dish for watching Sky on the flatscreen TV while parked in some remote location.

The basics

Most have a fridge, gas cooker, and shower and toilet combination. Ex-rentals come with these basic necessities but the options are almost limitless with custom-made and new vans.

Ross's European-designed Fiat (pictured) has a separate shower and toilet, which he says was hard to find in locally designed vans. Ross has a standard factory-built model but the only improvement he could think of was that "a bigger fridge might be nice".

Diana's custom-made van doesn't lack any home comforts and she's recently added a washing machine.

Hot-water systems and fridges are usually two- or three-way powered, running on a combination of gas and/or battery and electrical power. Electrical power is provided via a cable when the van is hooked up to a 240-volt supply; and when there's no mains power, the battery or gas kicks in to keep things running. The battery recharges while you're driving or plugged into the mains - which ensures your fridge is always running, even when the van isn't.