If that is really the scope of works he is undertaking, $5k is not expensive. Considering the following points : 1) 3D drawings cost around $100 PER View. Considering 2 views per room, 11 rooms x 2 = 22 views, = $2200 ( This is the cost if you were to engage a Professional ID to do the design.) Then the detail drawings which are included should be valued at around $1000 if it's the proper detailed construction drawings, not freehand sketches, and should be about 50 pages. 2) Site co-ordination Fees. I guess your new home is at least a 3-storey landed property, meaning that it'll take at least 6 weeks for a new unit or 10~12 weeks for a resale unit. Considering the time to travel and time on co-ordination to be spent, the remaining $1800 is reasonable. It's best to request him to draft a contract specifying the scope of works in detail, e.g 1) What if the design he provides is not what you expect, how many time of changes is allowed etc. 2) What are the clauses for termination of contract in the event that e.g he cannot produce a reasonably satisfactory design etc. 3) Any Late Delivery charges since he's undertaking the co-ordination work. Who should be responsible for the Appointed Contractors' schedule, material quality and workmanship? 4) Since he's only doing the design and co-ordination, how and who is to arbitrate if the design cannot be fabricated?