I'm about to go on my 1st 3 day tour and whilst initially thinking I could get away with what I had will probably need a seatpack or something like one of these
https://www.evanscycles.com/topeak-b...e-bag-EV345022

I've absolutely no idea what size I may need though, I've got tools, spare tube / pump etc in a small frame bag and initially I was thinking just shower gel / toothpaste and a couple of pairs of grundies in something else as hopefully the accommodation we book will probably provide towels.

I suddenly thought I don't really want to go and eat in cycle specific clothing in the evenings but want to travel light as light as possible (so can probably leave the hairdryer and kitchen sink at home ) ... but I'm guessing I probably want 1 shirt / t-shirt as it's just 2 evenings and won't be wearing it during the day and maybe a pair of jeans .. the one other thing I thought may be a good idea was a spare tyre just in case ... although we're not going that far from civilisation,

Anything I've missed and what size pack might I get away with and any recommendations to seatpacks much appreciated???