There are mortgage options now available that only require a down payment of 5% or less of the purchase price. But the larger the down payment, the less you have to borrow, and the more equity you'll have. Mortgages with less than a 20% down payment generally require a mortgage insurance policy to secure the loan. When considering the size of your down payment, consider that you'll also need money for closing costs, moving expenses, and possibly repairs and decorating.
Using thin wood wafers called biscuits can strengthen wood joints by providing more glue bonding area. You can use a biscuit joiner (also called a plate joiner) to cut precision mating slots in boards for the biscuits, which are available in three sizes. Or, to save money you can buy a kit to convert either your router or right-angle grinder. The conversion kits will generally cost about half that of a dedicated biscuit joiner.