Please enquire whether any sows you buy have been with boars over 3 weeks old at any stage. Sows can become pregnant from 4 weeks onwards.
Here is a website with lots of pictures for sexing. Always check any piggies when you bring them home to avoid problems from missexed guinea pigs. You can also post pictures of the vital bits in our pregnancy section if you want confirmationfrom some very experienced rescue people on this forum.
http://www.cavyspirit.com/sexing.htm
Please get the biggest
rabbit cage that you can get. Here in Britain, the minimum recommendation for two guinea pigs is 60cmx120cm. It would be great if you came as close as possible to that! I know that it is much more difficult in Eastern Europe. You may find cheaper deals on the internet, so it is worth having a look.
Don't buy shop treats; seeds, dairy (including yoghurt) and sugar are big no nos! Avoid wood chipping for bedding - it can cause respiratory problems. If you can, use fleece (acrylic or polyester bed throws from the supermarket with a 100% cotton underlay (towels, mattress covers, incontinence pads) as bedding and just get a flattish plastic box for the hay tray. Look in our housing section for inspiration.
Get pellet food rather than muesli and good quality hay - 80% of the daily food intake should be hay. Don't buy additives for water; guinea pigs tend to drink less, you can't control the intake and the additive will only help to produce green algae in record time.
PS: We would be greatful if you put your country in your profile; that way, we can avoid misunderstandings and giving you the wrong advice. You can do this in User CP/edit profile/location.