Hiya
You have alot of different issues going on here but I'll answer what I can about our situation
I have PCOS, fibro and HMS, we were told the HMS wouldn't not impact our chances of having a child-just the pcos/fibro issue. It took us 7 years, alot of drugs and 4 cycles of ICSI to conceive but she is worth every minute and every penny. I must add everyone's level of PCOS is different and we had factors on my husbands side too so please don't think I'm suggesting the only way is through IVF!
Finances are a big issue for anyone having kids I guess but HMS does make things even harder

. Do you have to remain the breadwinner? Is there anything you could do to plan ahead between you, better qualifications to get better jobs/less hours for the same pay? I know you are desperate to start now, and I do appreciate how broody you can get believe me, but in a way having to wait the 7 years we did meant our financial situation was better when we did finally have CJ.
In a way having to work still-I do 3 to 4 days a week, helps my hms, they are days off the lifting etc when I can sit at my desk (and have an adult conversation!)
Physically oh yes its hard-but so so rewarding. Yes certain things are tiring and hard but with babies/kids they keep moving on, progressing to the next stage so I just had to tell myself "this too will pass" I knew it would be easier once she slept through the night, sat up by herself, crawled so at each stage her needs, and the demands on me have changed. I'm looking forward to her walking now, that will definitely help my joints
We have decided to stop at one-I know I couldn't cope with 2 kids at diffeent ages, but I know alot of HMS mums who do a fantastic job.
Do you have family nearby who would be able to help out? I've heard good things about Homestart
http://www.home-start.org.uk/homepage, it might be worth ringing them now to find out what sort of help is available
Sorry got to go cook tea but if I think of anything else I'll pop back here again.