I am a sole trader and run a tattoo studio. I work there and rent out a chair in the studio. The tenant has his own client base, handles all his own money and has his own insurance. Any customers who walk in off the street are allocated to whoever is free unless they have a preference. The tenant does use my consumables, but this was taken into account when deciding on his weekly rent charge. Is the income I receive from the tenant subject to National Insurance contributions (as part of my trade) or not (as rental income)? 

Arthur Weller replies:
If you look at HMRC’s Property Income manual (at www.gov.uk/hmrc-internal-manuals/propertyincome-manual/pim4300) you can see that you are allowed to treat this income as rental income. The charge for use of consumables is presumably secondary to the main charge - the rental of the chair. See from PIM1051 that the definition of rental income is wide ranging. See also HMRC guidance at www.gov.uk/hmrc-internal-manuals/vat-landand-property/vatlp19800 for the VAT implications of what you are doing.