Bugger. Bigger lumps than expected are, unfortunately, all too common. Particularly if you have lobular BC. The actual pathology will determine what sort of treatment you will have. The sequencing changes according to all manner of circumstances. Do you know if you need more surgery?
Chemotherapy usually comes first, but then sometimes it doesn't. You really wont know until you speak to your oncologist.
On the topic of oncologists, it is important to ask what options you have there. It is possible you have access to a public service--do find out if that is the case as we are sometimes not fully informed about all available services. Surgeons tend to follow their own referral pathways, and that can be very expensive if they send you to a private practitioner when there is a public option.
Chemo itself wont cost you anything, the appointments with specialists do.
Trying to prep for these things is both stressful and, frequently, pointless. It sounds like your main concerns are going to be your husband and your farm. Concentrate on putting a few different plans together to make sure you have some support there. You won't know how treatment will affect you until you start. It is quite possible you will cruise through this, or at least have an easier time than you expect. Chemo is not like it was even 10 years ago and many people have few, and manageable, side effects.
I would recommend getting a port installed if it is possible or appropriate for you. They are not fail proof, but can greatly improve your chemo experience.
Get yourself a good big folder, keep copies of absolutely everything in it and take it to every appointment. Get copies of all your test results, collect business cards, write down peoples names, when you saw them and what you spoke to them about. Keep records of any side effects and what was done about them. I know this sounds like a lot of work, but it surprising how often results and reports don't get forwarded to the right people so it pays to take control of that yourself. You think everything is going to be seared into your brain and you will remember it all, but this is going to be a long haul, so keep good records.
If you haven't already connected with a breast care nurse, chase that up straight away. they can be a godsend.
Above all, take time for yourself. That might mean scheduling a daily walk where you don't think about anything except putting one foot in front of the other for a few kms. Good luck. Mxxx