If you decide to do all the work not immediately, but for now, for example, to dwell on drilling, you should choose the company that offers an acceptable price for this type of work. At the same time, pay attention to the fact that the price is indicated taking into account VAT and expenses for transport services, otherwise it is sometimes retroactively learned that this information was printed in the contract with small print, and you have to bear additional costs. In any case, a full calculation of work on the well will help you.