If you post the picture as an extra comment people will be able to see it better

These are modern examples, but plenty spanish (vacation) houses have external stairs. I like the second modern example best, as the roof height difference integrates the terrace, makes it look like part of the house rather than 'mere railings' on top of a bungalow.

Plans drawn however concerns re size of extension in comparison end of bungalow which is staying as is , this side is attached to neigbour , depth of 3m from original front door , plan is 2 by 5 m across front . any suggestions . many thanks

For costs: you are looking at approx 6 square meters and anticipated typical costs for construction in the UK in 2022 are between £1,750 and £3,000 per m2 depending on where you are and what you do. For example kitchens, bathrooms and utility rooms tend to cost more than other types of rooms because they have more fittings, services and more expensive finishes. To complete your project within budget you'll find the Renovation Roadmap workshop I'm running on Friday 27th January really useful. It's only £47, all profits go to the homeless charity Coffee4Craig, and the workshop includes Q&A with me so you can get many of your questions answered. Find out more and save your spot here: https://iarchitectlimited.vipmembervault.com/products/courses/view/1145853 Jane chartered architect eco-home and conservation area specialist www.i-architect.co.uk