Some of the things that you will need to ask will be dependant on what you are using the venue for (ie -is it just for ceremony/just reception/all? Are there places for the guests to stay as well, is it a hotel)
Your questions are all good, I'd add the following:
Do you have to use their in house caterers or are you free to choose your own? Can you do some catering yourself (we wanted to add cheese and biscuits as an option for either after dessert or as part of evening buffet, but had to use their catering staff for everything - and to get cheese and biscuits through them was extortionate - would have loved to pop to tescos and provided our own stuff but it wasnt allowed)
Are vegetarians adequately covered? Check for both wedding breakfast and evening reception - our hog roast in the evening made no concessions for veggies, we had to persuade the venue to provide veggie bangers (which they then forgot to cook!)
Will they assemble the cake, or do you have to do it? Do they provide a cake stand?
What do they provide for table stationary etc - table numbers (if you dont have your own), table number holders? Table plan easel?
Do they have an in house wedding planner that will run things on the day for you, or do you have to rely on your best man and other members of the wedding party to run things?
Are you having a band? Disco? planning on plugging in your i-pod/laptop into their sound system? You'll need to find out logistics for those sorts of things, what do they provide vs what your band/mobile disco might provide.
Do they have an option for in-house wine or corkage, or storage and handling costs - can you choose? You can get better deals if you provide your own wine and pay corkage, but then need to consider, do you need to hire glasses - again does it have to be through them or can you source your own?
Do they have places to stay the night before/after, if you or your guests want to stay onsite? What time can you access the venue on the day to get ready? Can you access the day before to set up things, deliver wine/cake/soft drinks etc?
It really is a huge topic, and i would recommend you try looking at some other forums like minimins- "You and Your Wedding" is one that i used a lot. (Be warned though, they don't have a search option like minimins does so it can be a struggle to find things that you want)
This was my venue by the way. It was on Sarah Beany's restoration nightmare a couple of months ago - it was the one she went to see to get ideas from a venue that does weddings really well (showing off I know, but i loved it!
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