I go on bursts, and specially depending on trips, events and family visits. No specific budget.
With my more targeted and spontaneous shooting habits sans travel, it tended to be about 1-3 rolls of color per month. Count 10-12 per half year that I sent out to the lab, and had scanned in some instances. Depending on the scans that's easily $150-200. GOing to budget concerns, $200 is some money and another hobby is travel or such, and that is almost enough to cover a well planned weekend getaway.
After some Asian trips where I had it done locally, the other rolls that didn't travel there were develop only. I I have about 15 rolls of color film not scanned frame by frame spanning back fall 2024. Have some flatbed contact sheets ready however... So for dev only at $6 give or take, it's just $60-70 per season. I keep procastinating the set up of digital scanning, perhaps when NLP comes out standalone...
B&W I am much more proficient, but that does not go to a lab. I stocked up on all types of films again from last summer film deals. About 15+15 rolls of B&W HP5 and D400, 10 of Kentmere, some other odds and ends (IR, CHS100II). Frozen fresh E6. C41 I am down to a couple Portra 160 rolls that are leftover from my travels and kept as speciall and somehow got a couple propacks worth of Gold 200 loose here and there. I hit a few rolls of it, fresh, of a local auction site and shaved off $2.5 each off what they go retail here.
Expired happens if it's my stock, I have even been burned by backing paper mottling in some Foma that was fresh but had been warm and humid in these travels; the other rolls too but thankfully not affected. I gave away the couple rolls left to a Toy camera user.
Ironically also I am a paper scavenger. I've either thrifted, been given, or used common donated paper of our photoclub. 20 year old Ilford MGIV RC does great workprints still. Last winter it was a couple boxes worth, about 200 sheets used. $250 give or take.