Stay inside or outside Kruger Park?

Apart from camping, the only budget accommodation options inside Kruger are the 2 huts at Lower Sabie, which are around R130 per night. I guess if you're doing a tour you may as well stay where it's convenient for them too. I haven't stayed outside Kruger but I think it looks feasible. Where have they suggested you stay?

Great thanks, I'll look into it more!

Personally, I feel that the whole point of going to the beautiful and relaxing Kruger Park is to spend the time immersed in the place- staying in the camps and spending days slowly driving spotting the game. Being South African, we'd go every year and it was a highlight to just chill out there.
With three days you can start near Letaba and work your way down to Lower Sabie, Skukuza, Berg-en-dal or do it the other way round- if you have a hire car/van. It's really interesting to see how over the distance, the terrain/vegetation changes and what animals are found where. We've always seen lions and leopards near Olifants/Satara and then near Lower Sabie you get to see long trains of elephant families walking. If you are based outside- would you be able to see as great an area?
I guess it depends what you're after. And what you can afford. But if you can, I'd recommend staying in the Park.

We were on a trip that stayed just outside the park (run by Acacia) and it really didn't make any difference - just an extra 20 min drive at the start and end of the day - we set out pretty early each day so didn't affect the amount of time in the park. This trip also offered the chance to do game drives in a private reserve bordering the park which also had it's own advantages - being able to drive offroad and a greater chance of seeing lions up close (the reserve had a couple of prides of lions and their whereabouts was monitored quite closely by the rangers.

It sepends on where your base is. I would normally stay inside the park, but I have also stayed outside (near Crocodile Bridge and near Phabeni Gate) and driven in every day. That is a schlep and one always does the same little section of the park. Stay inside the park at selected camps - Letaba, Satara, Lower Sabie, would be my choice (in either direction) - and enjoy it properly. If you have to stay outside make sure the place at which you stay is right there, within a few kilometres of the entrance - not so many kilometres away that you cannot possibly get there when the gates open.