Sarathaji, first of all do you think there is space in your guest bedroom for a attach bathroom as the standard size required for a bathroom is minimum 4'6" x 6'6".

Where is the utility room in the drawing?

As per the present drawing, your dining room is on the other end which isn't practically possible.

You must rethink as this plan is not made taking care of of your requirements.

For any help, feel free to ask me.

haha you have a great problem! refer to the attached sketch plan,roughly 12'x6'10" will be your kitchen and utility you can accommodate a fridge, a washing machine, sink for washing utensils. keep it combined kitchen + utility. for guest bedroom, bathroom will be 4'x6'10" exactly, comfortable and as per standards. and my suggestion would be keep the living as living as by going the changes to kichen area you will get a wall where you can mount a TV . and placing a small dining table will serve as breakfast table, and also use your dining room as a study our your own personal leisure space. and about the costing part, there will be a lot of civil work involved , demolition, water proofing of new bathroom, plumbing for bathroom, new accessories new tiles. consider a range amount of 10 lakhs to 20 lakhs depending upon finish, chosen contractor rates and specifications. these are very rough figures.

I would prefer if u mention the exact requirement.. List One by One... that will add on the total cost of the project...