There are basically five options for flooring a marquee:
Wooden/suspended floor, carpet, matting, plastic tiling or breathable flooring (softex etc).
The best finish is a wooden floor with new exhibition carpet on top, it's also the most expensive.
The worst in my opinion is breathable flooring as it allows condensation to build up.
We once got called out my a lady complaining her marquee leaked when we were in the middle of a hose pipe ban and it hadn't rained for 2 weeks! She'd watered her lawn just before we'd arrived, she didn't have any flooring so it all came off as water vapour forming as condensation up in the marquee.
If you use wooden flooring, carpet or matting you should lay a groundsheet or polythene underneath to prevent this happening. Breathable is exactly what a floor shouldn't be! Grass is tough stuff, it recovered soon after the marquee's gone.
Larger marquees offer an integrated flooring system or use an interlocking wooden floor.
This is what most marquee company's use for most jobs. Lasts for years, just hoover it after laying (we used to use a leaf blower), put a groundsheet underneath & nail it all down with 4 inch or 6 inch nails.
Offered as a premium option to matting it's laid in exactly the same way but you only get 1-3 uses out of carpet depending on the colour and intensity of use. Recyclable options now available as it is becoming increasingly difficult to dispose of.
I was never a fan as it hides dips and holes until trodden on but other people swear by it. Bulky but easy and quick to lay.
Hate it. Keep it for caravan awnings.
If you're starting up a hire company I'd recommend buying some coconut matting. You can also offer carpet and you just price it for buying it new and only using it once. I'd also buy some wooden flooring to use as dance floors then when you have enough you can offer it as a solid floor.
In general there's no need to have a solid floor during the summer. For my wedding I had carpet over groundsheets on grass and everyone walked in thinking it was a solid floor underneath. The only exception would be on patios or tennis courts that might get water pooling.
Thanks for reading