Without even looking at the sheet I can already tell you that you WILL forget to order stuff and you WILL go over budget
Looking at the spreadsheet I notice that you have a gas cooker but no propane bottle / tank. I also notice that there isn't a vapour barrier listed. You might also want to consider some sound proofing such as rattletrap or similar.
There's also nothing in there for furniture (timber? / 80-20?) or bedding or any entertainment (will you want a TV or projector, bluetooth speaker? Raspberry Pi or other micro PC built in somewhere, will you want a satellite dish or WiFi hotspot for internet, or maybe built in speakers in the back doors or ceiling etc?).
You have solar panels, but no cable entry gland.
I would also suggest that you put in some circuit breakers / isolator switches. I have one which kills the solar power before it hits my MPPT controller, one which isolates the leisure batteries from the alternator charger / vehicle battery, one which isolates the leisure batteries from the fuse box, one which isolates my secondary fuse box in my charging station (a lockable area for phones and gadgets etc). Everything can be isolated from everything else.
You also don't seem to have curtains or any privacy screens.
I also added a couple of fire extinguishers and a fire blanket to my build.
I'm not seeing a sink or tap listed or any water filtration system.
Will you be installing a toilet of some description?
How about an awning? Bicycle rack? Spare wheel mount on rear doors?, roof rack?, ladder? Light bar? Air horns (compressor for them can double as a tire inflator - I'm soooo tempted)
I would also spend some time now looking at your wiring requirements in quite a lot of detail.
I didn't know enough about voltage drop in 12v systems and ended up replacing a lot of cabling for thicker stuff.
Knowing exactly what needs to go where and how thick the cable needs to be is worth doing right away.
I would also make a plan of the sequence of work you are going to do so you can plan what to order and when.
Unless you have a lot of storage space ordering it all at once is likely to be overwhelming.
I'm guessing that the build will go something along the lines of:
1) Strip everything out, deal with any rust and mechanical work the van might need.
2) Cut holes for the windows and skylights and get those installed first. It's easier to pick up any metal filings now than when you've started panelling the van. Make any holes you want for roof mounted antennas and for your solar cable entry glands. Now is also the time to make any holes you want for drainage or drop out vents or to bolt furniture or seating or L track through the floor. Any other holes in your van for water fill points, electrical hookup, cassette toilets or whatever. Will you be mounting the solar panels on something like Unistrut? Now's the time to make the holes and mount that channel.
3) Put in your rattletrap, insulation, vapour barrier, wiring and plumbing and panelling.
4) Install gas / water / electrical systems
5) Build cabinets / cupboards / furniture / bed
You will inevitably also learn how to play postal roulette.
The rules are simple:
During the day, think of as many things as you can which you will need for your next part of the project and keep adding them to your cart in eBay / Amazon.
At the end of the day checkout and pay for it all.
You win points for every item that arrives in time or ahead of time and you lose points for every item which arrives late and holds you up.
You lose double points for things you should have ordered but forgot to, you lose treble points for anything you double ordered and as the 'Joker' you win or lose quadruple points for items ordered from China depending on if/when they arrive and if they work when they get there.
You will get a lot of stuff wrong, you will end up doing stuff twice, or three times. You will change your mind about where stuff should go or realise that something you planned simply won't work.
That's just part of the journey. There's a wealth of knowledge and experience on here - there are five ways to approach every task and ten people who will insist that theirs is the best way to do it
. You will end up buying a bunch of tools you hadn't thought of and in my case even some I didn't know existed (plunge saw and track was a revelation)
I'm sure I've missed a few things - but hopefully that's been helpful.
Keep asking and keep letting us know how you're getting on.
