You can buy stainless steel BBQs that fold flat and rest on bent wire legs for £10 online. They fold flat and could even be packable for touring. Good for charcoal cooking then switch to wood for the evening fire pit. Backwoods TV!
Saw a small folding legged fire pit for £35 with grill and screen mesh cover for after cooking fire. I've seen lots of these in campsites this year but not as many previous years.
Whatever disposables use to aid lighting.will be volatiles that get burnt off before cooking. As said the briquettes might be the issue due to their forming with possibly fly ash waste. That's cheapo garage ones. Either way real charcoal burns better and is easier to light IME.
Short of lugging around a sack of your favourite green, organic, fairtrade hug the planet charcoal from your secret supplier any lump wood charcoal will be good in any reusable BBQ with sufficiently long legs to prevent scorching, we have a £10 mini folding barrel one which opens to give two mini half barrels, twice the cooking space. Great for 5 or more, especially since you mostly cook a bit, eat a bit then eat more. You never really cook all the food at once. IMHO BBQs need to be long running affairs that lasts hours. Firmly believe BBQs to be half entertainment, half sustenance.
P.S. those pot bellied, cast iron BBQs were the popular type a good few years ago. Now it's fire pit types I reckon. Fashion BBQs!