I used Moneysoft Payroll Manager to complete the payroll exam. It is a pretty good package, though for some reason they have removed the ability to advance holiday pay so you have to work around that. It has a free 30 day trial which is plenty of time to get used to the software and complete the exam if you have already familiarised yourself with the theory.
The tax exam is purely theory, no computerised sections so no need for a package to do that.
For the computerised sections of the main qualifications I used QuickBooks Online which has all the reports you could possibly need. Again, this is available on a 30 day trial for free which gives you time to do one of the exams. Pretty much all the major software has a free trial so trying out different ones for different exams gives you a chance to test which you would prefer to use in your own work. I had never used Sage before and didn't really get on with it but if you used that in your previous roles you may feel differently.
Not done the costing exam as have loads of experience in costing from previous jobs and to be honest it is never something clients have appeared particularly interested in.
As far as my setup for work generally, software I use is:
VT Transaction+ - one off license, dead simple to use and good for just chucking loads of transactions in. Looks old school and limited reporting but good for clients who just want their bookkeeping done annually.
QuickBooks - for clients who want more regular bookkeeping and reports etc. Worth becoming a ProAdvisor as it is free, you get a free copy of QBO for yourself, training in using the programme and they will reimburse £150 of advertising/promotional costs which is great when you're just starting out.
AutoEntry - for scanning invoices to upload to VT/QuickBooks where this is (a) quicker than doing ti myself (b) something the client wants to use. To my mind, more flexible and value for money than Receipt Bank but others may think otherwise.
Payroll Manager - for payroll. Only just qualified for payroll but like I say this looks good.
Taxfiler - Not started doing SATR's yet but having looked through the offerings Taxfiler appears to be the best VFM option for a small operation and gets pretty good writeups.
Hope that all helps.
Edited at 17 Oct 2017 09:55 AM GMT