This is exactly what we planned to do!
Recognising that it was going to cost quite a bit - and the need to convince myself that it was worth it - I thought I would try to get as close to the final set up as possible to try out.
In doing that I now have a setup that works for us, isn't 100% as good as the 'proper' solution but good enough for us and cost a fraction.
Since we have now been on 3 full trips using this with no thought yet of needing to upgrade I thought I would post the details in case others want to give this a try.
These are the components:
Chairs:
We also chose to use the Front Runner Expander chairs but sourced in the UK from John Craddock:
CHAI007, front runner expander telescopic chair for Defender 90/110, Discovery 1, Discovery 2, Discovery 3, Discovery 4, Freelander 2, Range Rover 2002-2009, Range Rover Sport 2005-2009, Evoque, Land Rover Parts and Range Rover Parts
www.johncraddockltd.co.uk
Bag / chair storage:
I found that the standard chair bag can be reduced using the built in straps and its still easy to slid the collapsed chairs beneath these. This replicates the metal tray and ensures there is good space for storage beneath.
Bed extension - limit lift needed:
Because we use the bed extension for bedding when travelling, opening this fully to extract chairs and table was a pain - and the gap unnecessarily large. While browsing the 1sternehotel website I noticed some clips that allowed just the first 'click' to be used and a free area beyond which means that the bed extension can be then lowered again without having to move to the end of the ratchet. This is absolutely a game changer for me as it makes is SO simple to extract the chairs and table even with bedding and other items on the stored on the extension. I now think the chairs and table storage is much better even than in the Cali we hired before getting our MP!
Here is a link to these clips on the 1sternehotel site:
Click & Slide - die Sperre für die Hettich Bettbeschläge des unteren Bettes im Mercedes-Benz Marco Polo W447 und Viano Marco Polo W639 im Mercedes Marco Polo Zubehör Shop 1sternehotel alles für den Mercedes Marco Polo
www.1sternehotel.de
Under bed drawers:
The pull out tray is easily the most expensive item in all this. Before getting our MP I was determined that I wanted a pull out tray and did a lot of research on what was available - discovering, as others have, that many German companies stopped shipping to the UK. This was the no 1 item I most wanted to justify the cost for and the only way I could think of replicating the drawer was with plastic boxes.
Finding ones that fit the space well was a real challenge, but in the end, and by chance, I found some under bed drawers that fit the front to back depth very well, and 2 side by side leaves only about 100mm space -which we have found useful anyway to store other items.
Unbelievably these drawers come from Argos! They do the job REALLY well. They slide out easily (the rubber mat is essential here I think - see next item), they can be removed easily both for pre loading and on site - or when not wanted at all. We do not use the supplied lids - which permits them the be 'over filled' height wise to maximise what's available. I haven't had issues with things spilling out with no lids.
What I set up as a temporary 'trial' has worked so well that its now hard (for us at least) to justify the expense of a 'proper' slide out tray.
Here is a link to the drawers on Argos (yes, they really are that cheap - but honestly brilliant!):
Mat on 'boot' floor:
Since its likely we will use the MP in bad weather combined with our habit of going for hikes regardless, I decided to get some rubber mats for the living / boot areas as a means to make cleaning easier / minimise damage to the camper.
As it turned out, because the boot mat covers the rails in the boot area, the drawers are not affected by the variation in height and rail gaps. (I haven't tried the drawers without the mat so this is speculation.) The pattern in the rubber also means the drawers have less of a tendency to roll back and forth (we use the space between then and tailgate to store things (shoes / boots) anyway, but even without this the draws seem to stay put.
I ordered the mats from the link below. They are good quality, fit well...but have a strong chemical smell that takes weeks to fade (I had a battle with my wife to keep the boot mat in the van so bad was this originally!). Just a warning about what is otherwise a good product.
Buy Tailored Mercedes V-Class 2014 Marco Polo Full vehicle floor Car Mats. Manufactured in the UK. Free UK Delivery. Plain or Personalised. Quality Guaranteed.
officialcarmats.co.uk
I have attached some pics. One shows the bed extension closed, the standard chair bag reduced and drawers below; one shows the bed extension in the reduced 'raised' position and finally a pic of the clips that permit the reduced raised position on the ratchet extension support arms.
As I said, I didn't set out to make this a full time solution - but has become so for us - at least for now. It's undoubtedly a compromise on the 'proper' slide and one day we may upgrade to one. But this has worked so well for us and transformed the usable storage in the boot area that I wanted to share it in the hope it helps others.