In my experience, forces bases hire bands through agents, so you need to find out who your local bases use and try to get on their books. My experience has been similar to BottomE's. Very much a drinking culture, but they treat and pay you well.
I had an interesting experience when looking for a 1x12 combo. Tried a few in the shop and the MB 121P was the best sounding by quite a margin. Was about to buy one when I spotted a Phil Jones C4 (4x5) in a corner. Asked what I was like and they plugged a baby GK head into it. Tried it and was amazed. It was louder than the Mark and the tone was much nicer. Ended up buying one and using it with my regular head for small gigs. Have since bought another and am picking up a third next week (my head will run into 2 ohms). Should give me a flexible set up that will handle most things.
Ah, memories. I put a couple of Black Widows in mine when the original drivers died. Not light, but what a sound. Couldn't carry it now at my advanced age.
He's pretty astonishing, isn't he? I don't like the band (not old git's music), but he's dynamite. I remember Ed Friedland did a piece on him on his YouTube channel and said he reckoned he'd (Ed) have tendinitis within a couple of weeks if he tried to play like Steve every night.
I have no problem with someone singing through my PA. I'd prefer it if they brought their own mic, but many do anyway. If not, they get my well used old SM58 that I keep for such eventualities (I don't loan them one of my condensers). As long as they're not head-bangers, it's not a problem. I'd just say fine if I was you.
"What's the least you'll accept?" is the chancer's line. They're always hoping to find someone who is desperate or who has no idea. The only answer is "What are you offering?" as others say.
If just for putting in the car and you're confident nothing will fall on it, the cheaper one should be fine. Googling "bass gig bag" will turn up plenty of options.
I think if you want aggressive, the amp will have more influence. Before spending Vand/Berg money on a cab, I'd visit the shops and compare some stuff.
Great basses those Thunders. For the money, there was little to beat them at the time. Agree with others about avoiding cheapies. Gotohs great value for what they are. CD Guitars in SE London v good for Gotoh. Google will find them. Get all my bits from them.
Just to add a further complication, a decent, accurate hi-fi sub is not cheap. Rather than get a cheapo, if you put the money you would have spent on it towards upgrading your hi fi speakers, the result will almost certainly be better.
Rehearsal 8 - 3 out of 5 arrived with no money???? Surely they knew there would be a room fee to be paid. Notice 2 were the singers, presumably the same singers who also missed your most recent to "take daughter to an audition". The p1ss is being taken, I suggest. Time to move on, imho. Don't bother to complain - they've heard it before and know they can continue to mess you about. Just say "See yer".