nah, i usually simply send an invoice if the entire amount is payed via paypal and set it to 'Partial payments'
i do not usually include due-dates,
as i alsways permit people to let me know when/ if they
have issues in their RL ( bills, doctor, medecine, vet andsoon) so that we can discuss to skip a payment or two to a later date,
i don't want to change and resent paymentplans as it creates a lot of work, so i simply for these possibilities, don't include due-dates : D
my advice when you are in a paymentplan with me therefor would be :
gather money, save up untill it is a reasonable amount ( maybe 80 usd) and then send a payment ( to many to small payments eat away my income due to paypal feed = D )