Budget
Scotland has plenty of Hostels, both the Scottish Youth Hostel Association SYHA (http://www.syha.org.uk/) and a large and developing network of Independent Hostels. Some of the buildings are very impressive, like the one on Loch Lomond and the Carbisdale Castle Hostel. The SYHA traditionally involved guests performing chores and a ban on alcohol. The new breed of independent hostels have eschewed these concepts, causing the SYHA to loosen up its attitudes too.
Camping is another inexpensive way of touring Scotland, though the unpredictable weather makes it less appealing than in some other countries. In remote areas camp sites can be a significant distance apart so buy an up to date guide and plan your route. Booking is not usually necessary except in peak season. Generally, the rule is the more remote the camp site, the better the scenery and the lower the cost. Some camp sites may provide only basic amenities. Camping rough is possible in remote areas, but observe local signs, and never camp next to a stream that could rapidly become swollen by overnight rain. Midges tiny biting insects can be a particular nuisance during August and September: the insects are harmless but incredibly irritating.
Bed and Breakfast accommodation is widely available, even in remote areas and some very good deals can be found. Many people consider these to be more friendly and welcoming than a hotel. Local tourist information centres will help you find a room for the same night, and you may expect to pay in the region of £25 per person per night for room and full Scottish breakfast. The Scottish Guest House and Bed & Breakfast Association GHABBA (http://www.guesthouseband...) have a range of Bed and Breakfasts and Guest Houses across Scotland.
If visiting the major cities, try staying in Falkirk or Polmont. Both are far cheaper than the hotels in Glasgow and Edinburgh, and only 1/2 hour away from both on regular train services.
The Premier Travel Inn chain of motels in Scotland are widespread, with double rooms priced at around £55. In cities these are likely to prove cheaper than a hotel.