Business owners concerned about rising costs have been warned to check on their service charges if they are planning to rent offices or commercial property.

Cheryl Leyser, head of commercial property at MFG Solicitors, said: "Service charges often represent an unpredictable expense that is out of the control of the tenant.

"In this economic climate more and more tenants are worried about the level of service charges. These costs are for services which are invariably carried out at the landlord’s discretion such as repair and maintenance and can fluctuate greatly from year to year.

"Often landlords do not put in the lease how their service charges are calculated – they simply state that tenants will be charged a ‘fair proportion’, for example – and this can lead to uncertainty among tenants on retail and industrial estates."

Ideally, tenants should grasp the nettle of service charges during initial negotiations and consider trying to get them capped to assist with budgeting.

Historically landlords have always resisted being tied down to specific service charges, but Ms Leyser said that in the current economic climate, and with the business rates changes which force them to pay for empty space, they may feel it is more important to have a tenant in place rather than have empty premises.

"If leases are short term, tenants should try to agree an inclusive rent so that they have more certainty and can budget more accurately. This is especially true of start-up businesses," she said.

"On the other side of the coin, landlords need to judge what expenditure they foresee to ensure they are not left out of pocket if a major repair is required.

"If there are substantial works required to access roads, or the common parts are in a state of disrepair, they could be left with hefty bills. This would need to be factored in to any calculations."

She also pointed out that tenants who have internal repairing leases, often where they have taken part of a building, may still be caught indirectly for repairs to the exterior through the service charge, a cost they were not expecting. A survey of the building should be considered in such circumstances to ensure they will not be facing a share of a bill for, say, a new roof.

"This is particularly relevant on short-term lettings and it highlights the importance of taking legal advice from an experienced commercial property lawyer when taking on any kind of commitment as a tenant.

MFG Solicitors has offices in Halesowen, Telford, Kidderminster, Worcester, Bromsgrove, Wellington, Cleobury Mortimer and Oswestry.