Planning to start this sometime soon, what are the things I'll need to prep in case indoors, outdoors etc?

The plan is to let go a lot of stuff for cheap as part of major house decluttering, does presentation matter or will I get away with labelling everything with masking tape and price?

And i need advice on car rental as well since the only car we have is most likely to be taken for a week for service and repairs during the sale.

I would love to do for our car but unfortunately, I only share one car with husband. And that car is already due for routine service as well as some repairs, so might as well settle the whole thing in one go. I would not be asking about rental if the car is readily available.