Or at least not pay for most of them, if you are a resident of the UK.
You really can get most of your travel injections for free in the UK. I managed to get Hep B, Hep A, Typhoid, Polio, Diphtheria, Tetanus, and Cholera from the NHS. You have to sometimes be a bit sneaky, and you really have to be persistent and know what you need, and research alot, so it takes time and energy but you can do it.
First you need to go to your Dr or nurse and ask for your immunisation history which they should have on record. Get them to check over what you have had, and if you missed anything important as a child (which hopefully you haven't). You will have had some of your immusations in school, if you can remember what they are thats great, if not check wether you have a crazy big scar on your arm entphalitus in a circle, if you have then congratulations you have had the BCG, and are therefore protected against TB!
Next on the list is Polio, Tetanus, and Diphtheria. Now you should have received all your booster shots in school, but if your unsure, get a jab, or if its 10 years or just under since you last got them, get a jab. The boosters only last 10 years, and polio is still floating around in South Asia. You need to ask your nurse to give you this one, but its should be free. If she refuses for whatever reason, go to a different clinic. Simple.
Typhoid is similar, but shots only last 3 years, so you will probably have to ask for this one too. Same as above go to the Nurse, and it should be free.
Now its time for Hepatitis A and Hepatitis B. One of the common vaccines is twinrix and is a combination of the 2. If your job involves working with people alot (so most jobs), you are entitled to this (especially if you work in care industry), again this should be free. Bare in mind, this is a scheduled 3 or 4 shot vaccine. The 3 shot one is over 6 months, the 4 shot one is over 28 days (on specific days), and then the last shot a year later. If your on a tight time limit go for the 28 days one, but just remember to have the last one a year later, and that should cover you for 5 years.
Lastly its cholera. Now you dont strictly, really need cholera unless your going into an outbreak, but since I'm traveling around India and South East Asia, I feel its a case of safe and not sorry. On the NHS website they state they will pay for Cholera vaccinations as it is something that could spread really quickly around the UK. The way I got my prescription was by filling in a prescription request form at my Dr's, and stating the reason I wanted Cholera was because I am going to an area of cholera. Then basically you have to wait to see if the Dr will give you a prescription. Mine did, and as a prescription on the NHS it cost £30 but if you do it privately it will probably cost you double that. The prescription is a liquid you have to drink and the dose is 2 "drinks" one week apart.
Now there will still be more injections you will need to get, but you will probably have to go to a specialized travel clinic for them, and just make sure you research fully what you need, and take enough time to budget, as they can be very expensive.
The 4 main ones seem to be
Yellow fever for instance you HAVE to have before going to certain countries!
Here is a link for the NHS Travel vaccine site, so check it out.