In England you need an electrical inspection done at outset of letting a property (but not annually) and an annual Gas Safety Inspection certificate. All soft furnishings (upholstery, sofas, mattresses etc) must be post 1988 iirc or pre 1950 (information comes under the DTI here ). You don't have to leave much at all and it may well not be maintained in the same condition if you do - you'd need to inventory everything you do leave and check the tenant in and out against that list. If you expect it to be immaculate when you return organise a professional clean at the outset so that they must do likewise.
You'd need whatever the Scottish equivalent is of a Shorthold Assured Tenancy which is for 6 months and rolls on with specified notice periods on either side - you could ask a solicitor to advise you. Take a deposit of the equivalent of between a month to 6 weeks' rent in advance, plus a month's rent in advance, consider a home lettings insurance policy to cover default of rent and some damage beyond wear and tear, maintain contents insurance for whatever you leave plus buildings, consider a service agreement with breakdown cover for gas appliances.
If you are not staying local you may still wish to employ an agent (I too have an inherent dislike but needs must) to keep an eye on the property, run credit and reference checks on potential tenants, do periodic inspections and arrange for repairs.
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