Denise,
It may be too late for me to respond but here goes.
Yes, take it
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I agree if you are going to rent another camera rent a 7D and lense you are familier with.
The first two weddings I did I charged only my cost. I made it clear that I had never done it so I would not charge them anthing but the cost of the film/processing. This was before digital
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As mentioned before if you are ever going to be a wedding photographer you have to start with a wedding at some point. You will probably never think you are ready. Ask any profesional and you'll find they make mistakes all the time. I recently did a wedding and forgot to shoot the rings. My wife woke up at 3 in the morning with that revalation
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. We had the couple bring their rings by later and did them.
I feel you will do a great job. I know you have the skill. Looking at much of your work you also have the artistic eye for it. I have to draw on my wife to help with that side of the business.
If it is not too late, take the job and just charge what it takes to rent the equipement you need. Once she shares here wedding photos with your watermark on her facebook, you'll be getting calls from lots of future brides. Then you start charging reasonable rates and make enough to buy that 5D you want
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