Budget?
I'm generally not a fan of installing window ACs on vans; the lack of vertical support always seemed sketchy to me, and van bodies lack the space to install a proper support bracket like on a house. However if you are 100% sure that you will be parked and not moving the van at all for 4 months, maybe you can build a bracket to support it on the ground. Make sure to get an inverter unit, otherwise the constant bang-bang-bang-bang of it turning on and off will keep you awake at night.
Alternatively, get one of Midea's hose-in-hose portable units, preferably the smaller 10,000 BTU/hr one. Use the hose outline to make a cardboard template, then cut an adapter template out of plywood and install it in a window. There might be someone on Etsy who sells one already.
The most vanlife friendly (and most expensive) option would be to buy an EcoFlow Wave 3. Sure it's only 6100 BTU/hr, but it does have an inverter, can be mounted outside, and there are plenty of hose adapters available for van windows.
I got this when my 41 year old AC started getting real loud in the summer of 2024. I replaced that unit and now use this in a large bedroom until I get the window unit it.
It works well. Looking back, I should have got the 14,000 BTU at that time but they didnt have any in stock. The phone App is nice. Much better that the Friedich.
Midea Duo 12,000 BTU (10,000 BTU SACC) High Efficiency Inverter, Ultra Quiet Portable Air
Midea duo is the move tbh, the cooling per watt is hard to beat for the price
Might help to [check some picks here](https://www.reddit.com/r/recsmatter/comments/1su7tdt/best_portable_air_conditioner_recommendation/) too if you wanna compare
hx87
