One I had a rough estimate of guests, the first “budget tool” I used was The Knot budgeter to start playing with numbers and see what all needs to be paid for. Things like venues and photographers are likely to have some prices listed on their site, so you can start to get a general idea for your area.
My FH and I also sat down with our parents, separately, to see what/if they would contribute, and he and I looked at our own finances given the amount of time before the wedding to see what we could save up. With those numbers (everyone’s contributing for us – all parents and us – and FH is putting in the most), I was able to start putting more concrete numbers to items on the list. Once I knew our total budget and what TK said we should spend on any given item, I really started looking at things with a clearer picture.
For example, I knew that TK said I should spend up to $X on a venue. If one I saw online cost $X+more, I knew I’d have to cut numbers somewhere else if I ended up going with that venue. I also knew that I wanted a friend to officiate the ceremony and a friend’s band to play for the reception, so those were numbers I was able to adjust immediately. Florists, photographers, caterers – those are harder numbers to nail down and vary greatly.
If you’re already looking at dresses/shoes and are leaning toward particular designer(s), see what their prices are and plug in those numbers too. Or, if you’re going a pre-owned/heirloom/discount route, plug in those numbers too.
To give you an idea of my planning timeline (not that there’s any right way)…
We got engaged last July and had our engagement party in September. We asked our wedding party by the end of the year. The first thing I actually booked was the venue (in January), and it’s a good thing, too – our date changed because of the availability of the venue. From there, I booked the caterer/coordinator and rentals (March) and the photographer (March). Then I found a dress (in March – I was surprised I found it so early) and bought it. We booked the cake baker in April and paid the deposit in June. We’ve talked with florists and stationers but we’re not really seeing what we want, so we’re probably going the diy/online route with bridesign.com and vistaprint.com. Future Mother-In-Law is working on the rehearsal dinner and just booked the restaurant (in June). The band and officiant, my friends, have known I wanted them since December, so they’re in. I’ve had a year to plan so far, and another year til the wedding.
I guess my biggest suggestion is to sit down with the families and talk guest list and financial contributions. Once you have an approximate guest list and the top end of your budget (like the PP said), the big picture might be easier to see. Hope this helps and happy planning!!